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Saarland Abitur Physics study materials
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Saarland Abitur Physics practice questions

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Question 1Mechanics

A car accelerates uniformly from rest to 20 m/s in 5 seconds. What is its acceleration?

  1. 4 m/s² Correct answer.
  2. 100 m/s²
  3. 0.25 m/s²
  4. 20 m/s²

Explanation

a = Δv/Δt = (20 m/s − 0 m/s) / 5 s = 4 m/s².

Question 2Mechanics

What is Newton's First Law of Motion (the law of inertia)?

  1. An object remains at rest or in uniform motion unless acted upon by a net external force Correct answer.
  2. Every action has an equal and opposite reaction
  3. Force equals mass times acceleration
  4. Energy cannot be created or destroyed

Explanation

Newton's First Law (law of inertia) states that an object remains at rest or continues in uniform straight-line motion unless acted upon by a net external force.

Question 3Mechanics

What is Newton's Second Law of Motion, expressed as a formula?

  1. F = m × a Correct answer.
  2. F = m / a
  3. F = m + a
  4. F = m − a

Explanation

Newton's Second Law states that force equals mass times acceleration: F = m × a.

Question 4Mechanics

What is the formula for kinetic energy?

  1. E_kin = ½mv² Correct answer.
  2. E_kin = mv
  3. E_kin = mgh
  4. E_kin = m/v

Explanation

Kinetic energy is calculated as E_kin = ½mv², where m is mass and v is velocity.

Question 5Mechanics

A 2 kg object moves at 4 m/s. What is its kinetic energy?

  1. 16 J Correct answer.
  2. 8 J
  3. 32 J
  4. 4 J

Explanation

E_kin = ½ × m × v² = ½ × 2 kg × (4 m/s)² = ½ × 2 × 16 = 16 J.

Question 6Mechanics

What is the formula for gravitational potential energy near Earth's surface?

  1. E_pot = mgh Correct answer.
  2. E_pot = ½mv²
  3. E_pot = Fd
  4. E_pot = m/gh

Explanation

Gravitational potential energy near Earth's surface is calculated as E_pot = mgh, where m is mass, g is gravitational acceleration, and h is height.

Question 7Mechanics

A 5 kg object is lifted to a height of 2 m (g = 9.8 m/s²). What is its gravitational potential energy?

  1. 98 J Correct answer.
  2. 10 J
  3. 19.6 J
  4. 49 J

Explanation

E_pot = m × g × h = 5 kg × 9.8 m/s² × 2 m = 98 J.

Question 8Mechanics

What is the law of conservation of energy?

  1. Energy cannot be created or destroyed, only converted from one form to another Correct answer.
  2. Energy is constantly being created from nothing
  3. Energy always increases over time with no limit
  4. Energy applies only to kinetic energy, not potential energy

Explanation

The law of conservation of energy states that energy cannot be created or destroyed in an isolated system, only converted from one form to another (e.g., potential to kinetic).

Question 9Mechanics

A ball is dropped from a height of 5 m (g = 9.8 m/s², ignoring air resistance). Using energy conservation, what is its velocity just before hitting the ground?

  1. ≈9.9 m/s, since v = √(2gh) = √(2×9.8×5) = √98 Correct answer.
  2. 5 m/s, using the height value directly as the velocity
  3. 49 m/s, using 2gh without the square root
  4. 98 m/s, using g×h×2 without any square root

Explanation

Using energy conservation: mgh = ½mv², so v = √(2gh) = √(2×9.8×5) = √98 ≈ 9.9 m/s.

Question 10Mechanics

What is the formula for momentum (Impuls)?

  1. p = mv Correct answer.
  2. p = ½mv²
  3. p = F/m
  4. p = m/v

Explanation

Momentum (Impuls) is calculated as p = mv, the product of an object's mass and velocity.

Question 11Mechanics

What is the law of conservation of momentum?

  1. In a closed system with no external forces, the total momentum before an interaction equals the total momentum after Correct answer.
  2. Momentum is always lost in any collision with no exceptions
  3. Momentum only applies to elastic collisions, never inelastic ones
  4. Momentum cannot be calculated for systems with more than one object

Explanation

The law of conservation of momentum states that in a closed system with no external forces, the total momentum before an interaction (e.g., a collision) equals the total momentum after.

Question 12Mechanics

A 3 kg object moving at 4 m/s collides and sticks to a stationary 1 kg object (perfectly inelastic collision). What is their combined velocity after collision?

  1. 3 m/s, since total momentum before (3×4+1×0=12) equals total momentum after ((3+1)×v=12, so v=3) Correct answer.
  2. 4 m/s, unchanged from the first object's initial velocity
  3. 12 m/s, using the initial momentum value directly as velocity
  4. 1 m/s, dividing incorrectly

Explanation

By conservation of momentum: (3kg×4m/s) + (1kg×0m/s) = (3kg+1kg)×v, giving 12 = 4v, so v = 3 m/s.

Question 13Mechanics

What is 'Reibung' (friction), a force encountered in mechanics problems?

  1. A force that opposes relative motion between two surfaces in contact Correct answer.
  2. A force that always accelerates an object forward with no resistance
  3. A force unrelated to surface contact
  4. A force that only exists in a vacuum with no surfaces present

Explanation

Friction is a force that opposes relative motion (or the tendency of motion) between two surfaces in contact, converting some kinetic energy into heat.

Question 14Mechanics

What is uniform circular motion, and what force is required to maintain it?

  1. Motion at constant speed along a circular path, requiring a centripetal force directed toward the center Correct answer.
  2. Motion in a straight line with no curvature
  3. Motion requiring no net force whatsoever
  4. Motion where speed constantly changes with no fixed pattern

Explanation

Uniform circular motion is motion at constant speed along a circular path, requiring a centripetal force (Zentripetalkraft) continuously directed toward the center of the circle to maintain the curved path.

Question 15Mechanics

What is the formula for centripetal force?

  1. F_z = mv²/r Correct answer.
  2. F_z = mv
  3. F_z = m/r
  4. F_z = vr

Explanation

Centripetal force is calculated as F_z = mv²/r, where m is mass, v is velocity, and r is the radius of the circular path.

Question 16Mechanics

What is 'Trägheit' (inertia), directly related to Newton's First Law?

  1. The tendency of an object to resist changes in its state of motion Correct answer.
  2. A force that actively pushes objects toward a new state of motion
  3. A term unrelated to Newton's laws of motion
  4. A property that only applies to objects at rest, never moving objects

Explanation

Inertia (Trägheit) is the tendency of an object to resist changes in its state of motion (whether at rest or moving at constant velocity), the underlying principle behind Newton's First Law.

Question 17Mechanics

What is Newton's Third Law of Motion?

  1. For every action, there is an equal and opposite reaction Correct answer.
  2. An object remains at rest unless acted upon by a force
  3. Force equals mass times acceleration
  4. Energy is always conserved in a closed system

Explanation

Newton's Third Law states that for every action force, there is an equal and opposite reaction force, acting on a different object.

Question 18Mechanics

What is the formula for work done by a constant force over a distance (when force and displacement are in the same direction)?

  1. W = F × d Correct answer.
  2. W = F / d
  3. W = F + d
  4. W = F − d

Explanation

Work is calculated as W = F × d, the product of force and the displacement in the direction of that force.

Question 19Mechanics

What is 'Leistung' (power) in physics, as distinct from work/energy?

  1. The rate at which work is done or energy is transferred, per unit of time Correct answer.
  2. A term identical to 'work' with no distinction
  3. A term unrelated to energy transfer
  4. A quantity that has no standard unit

Explanation

Power (Leistung) is the rate at which work is done or energy is transferred, per unit of time, calculated as P = W/t (or equivalently P=E/t), measured in Watts.

Question 20Mechanics

What is 'Beschleunigung' (acceleration) as a physical quantity?

  1. The rate of change of velocity with respect to time Correct answer.
  2. A term identical to velocity with no distinction
  3. A quantity unrelated to motion
  4. A quantity that is always zero for any moving object

Explanation

Acceleration is the rate of change of velocity with respect to time (a=Δv/Δt), describing how quickly an object's speed or direction of motion is changing.

Question 21Mechanics

What does a velocity-time graph's SLOPE represent?

  1. Acceleration Correct answer.
  2. Distance traveled
  3. Total time elapsed
  4. Mass of the object

Explanation

The slope of a velocity-time graph represents acceleration (Δv/Δt), since slope is defined as the change in the y-axis value (velocity) divided by the change in the x-axis value (time).

Question 22Mechanics

What does the AREA under a velocity-time graph represent?

  1. The distance (or displacement) traveled during that time interval Correct answer.
  2. The acceleration at that specific moment
  3. The object's mass
  4. The object's momentum at a single instant

Explanation

The area under a velocity-time graph represents the distance (or displacement) traveled during that specific time interval, since distance equals the integral of velocity with respect to time.

Question 23Mechanics

What is 'Trägheitsmoment' (moment of inertia), relevant to rotational mechanics?

  1. A measure of an object's resistance to changes in its rotational motion, dependent on mass distribution relative to the axis of rotation Correct answer.
  2. A measure identical to linear mass with no connection to rotation
  3. A term unrelated to rotational motion
  4. A quantity that is always identical regardless of an object's shape

Explanation

Moment of inertia (Trägheitsmoment) is a measure of an object's resistance to changes in its rotational motion, analogous to mass in linear motion, but crucially dependent on how that mass is distributed relative to the axis of rotation.

Question 24Mechanics

What is 'Impulserhaltungssatz' applied to an elastic collision, in terms of what quantity is ALSO conserved beyond momentum?

  1. Kinetic energy is also conserved in a perfectly elastic collision, unlike in an inelastic collision Correct answer.
  2. Mass is converted to energy in every elastic collision
  3. No quantity beyond momentum is ever conserved in any collision type
  4. Heat is always maximized in an elastic collision

Explanation

In a perfectly elastic collision, both momentum AND total kinetic energy are conserved, distinguishing it from an inelastic collision where momentum is conserved but some kinetic energy converts to other forms (heat, sound, deformation).

Question 25Mechanics

What is the correct meaning of 'schiefer Wurf' (projectile motion at an angle), a classic mechanics problem type?

  1. Motion of an object launched at an angle to the horizontal, combining constant horizontal velocity with vertically accelerated (gravity-affected) motion Correct answer.
  2. Motion that occurs only in a perfectly vertical direction with no horizontal component
  3. A term unrelated to projectile motion
  4. Motion where both horizontal and vertical velocity components change due to gravity

Explanation

'Schiefer Wurf' (projectile motion at an angle) combines constant horizontal velocity (no horizontal force, ignoring air resistance) with vertically accelerated motion due to gravity, producing the characteristic parabolic trajectory.

Question 26Mechanics

What is the correct meaning of 'Gravitationsgesetz' (Newton's law of universal gravitation)?

  1. Every mass attracts every other mass with a force proportional to the product of their masses and inversely proportional to the square of the distance between them Correct answer.
  2. A law stating gravitational force is completely independent of mass
  3. A law unrelated to gravitational attraction
  4. A law that applies only to Earth, with no broader universal application

Explanation

Newton's law of universal gravitation states that every mass attracts every other mass with a force proportional to the product of their masses and inversely proportional to the square of the distance between their centers (F = Gm1m2/r²).

Question 27Mechanics

What is the correct meaning of 'Gewicht' (weight) as distinct from 'Masse' (mass) in physics?

  1. Mass is the amount of matter in an object (constant everywhere); weight is the gravitational force acting on that mass (varies with local gravitational field) Correct answer.
  2. They are identical terms with no distinction
  3. Weight is constant everywhere in the universe; mass varies depending on location
  4. Neither term has any connection to gravity

Explanation

Mass (Masse) is the amount of matter in an object, remaining constant regardless of location, while weight (Gewicht) is the gravitational force acting on that mass (W=mg), which VARIES depending on the local gravitational field strength (e.g., less on the Moon than on Earth).

Question 28Mechanics

What is 'Druck' (pressure) as a physical quantity, and what is its formula?

  1. Pressure is force per unit area, calculated as p = F/A Correct answer.
  2. Pressure is force multiplied by area
  3. Pressure is identical to force with no distinction
  4. Pressure has no standard formula or unit

Explanation

Pressure (Druck) is defined as force per unit area, calculated as p = F/A, measured in Pascals (Pa).

Question 29Mechanics

What is 'Trägheitskraft' (also known as a pseudo-force or fictitious force), as experienced in a non-inertial (accelerating) reference frame?

  1. An apparent force experienced by an observer in an accelerating reference frame, which does not arise from a genuine physical interaction Correct answer.
  2. A genuine physical force identical in nature to gravity or friction
  3. A term unrelated to reference frames
  4. A force that only exists in a stationary, non-accelerating reference frame

Explanation

A Trägheitskraft (pseudo-force/fictitious force) is an apparent force experienced by an observer in a non-inertial (accelerating) reference frame - such as feeling pushed back into a car seat during acceleration - which does not arise from a genuine physical interaction but from the frame's own acceleration.

Question 30Mechanics

What is the correct meaning of 'Inertialsystem' (inertial reference frame)?

  1. A reference frame in which an object with no net force acting on it moves at constant velocity (or remains at rest), consistent with Newton's First Law Correct answer.
  2. A reference frame that is always accelerating with no exceptions
  3. A term unrelated to Newton's laws
  4. A reference frame that only exists in outer space, never on Earth's surface

Explanation

An inertial reference frame is one in which an object with no net force acting on it moves at constant velocity (or remains at rest), consistent with Newton's First Law - a non-accelerating frame of reference.

Question 31Mechanics

What is the correct meaning of 'Zentrifugalkraft' (centrifugal force) as experienced by an object in circular motion, from the rotating object's own reference frame?

  1. An apparent (pseudo) force felt outward from the center, arising specifically in the rotating (non-inertial) reference frame Correct answer.
  2. A genuine physical force pulling objects toward the center of rotation
  3. A term unrelated to circular motion
  4. A force identical in every respect to the centripetal force

Explanation

Centrifugal force is an apparent (pseudo/fictitious) force felt outward from the center of rotation, but it only arises specifically when analyzing motion from the ROTATING object's own (non-inertial) reference frame - from an outside inertial observer's perspective, only the real, inward-directed centripetal force is acting.

Question 32Mechanics

What is the correct meaning of 'Federkonstante' (spring constant, k) in Hooke's Law?

  1. A measure of a spring's stiffness, describing how much force is required to stretch or compress it by a given distance Correct answer.
  2. A measure of a spring's total mass with no connection to stiffness
  3. A term unrelated to spring behavior
  4. A constant that is identical for every spring regardless of material or design

Explanation

The spring constant (Federkonstante, k) measures a spring's stiffness, describing the force required to stretch or compress it by a given distance, as expressed in Hooke's Law: F = k × x (or F = -kx, accounting for the restoring force direction).

Question 33Waves Optics

What is a 'harmonische Schwingung' (harmonic oscillation), a fundamental concept in wave/oscillation physics?

  1. A periodic motion (like a pendulum or spring) where the restoring force is proportional to displacement from equilibrium Correct answer.
  2. A motion with no periodic or repeating pattern whatsoever
  3. A term unrelated to periodic motion
  4. A motion that occurs only in electrical circuits, never in mechanical systems

Explanation

Harmonic oscillation is periodic motion (such as a pendulum or a mass on a spring) in which the restoring force is proportional to the displacement from equilibrium (following Hooke's law for springs), producing characteristic sinusoidal motion over time.

Question 34Waves Optics

What is the formula for the period of a simple pendulum's oscillation (for small angles)?

  1. T = 2π√(L/g) Correct answer.
  2. T = 2π√(g/L)
  3. T = 2πL/g
  4. T = 2π(L+g)

Explanation

The period of a simple pendulum (for small oscillation angles) is T = 2π√(L/g), where L is the pendulum length and g is gravitational acceleration.

Question 35Waves Optics

What is 'Resonanz' (resonance) in oscillation physics?

  1. The phenomenon where a system oscillates with maximum amplitude when driven at its natural frequency Correct answer.
  2. A phenomenon that occurs only when a system is driven at a frequency far from its natural frequency
  3. A term unrelated to oscillating systems
  4. A phenomenon that always decreases a system's oscillation amplitude

Explanation

Resonance is the phenomenon where an oscillating system responds with maximum amplitude when driven by an external force at (or very near) the system's own natural frequency.

Question 36Waves Optics

What is 'Brechung' (refraction) of light, an optics concept?

  1. The bending of light as it passes from one transparent medium to another with a different optical density Correct answer.
  2. A phenomenon where light always travels in a perfectly straight line with no bending regardless of medium
  3. A term unrelated to light behavior
  4. A phenomenon that only occurs with sound waves, never light

Explanation

Refraction is the bending of light as it passes from one transparent medium to another with a different optical density (refractive index), such as light bending when passing from air into water.

Question 37Waves Optics

What is 'Reflexion' (reflection) of a wave, such as light or sound?

  1. The bouncing back of a wave when it encounters a boundary or surface, without passing through it Correct answer.
  2. A phenomenon where a wave is completely absorbed with no bounce-back at all
  3. A term unrelated to wave behavior
  4. A phenomenon that only occurs with light, never sound

Explanation

Reflection is the bouncing back of a wave (light, sound, etc.) when it encounters a boundary or surface, following the law of reflection (angle of incidence equals angle of reflection).

Question 38Waves Optics

What is 'Interferenz' (interference) of waves?

  1. The superposition of two or more waves, resulting in a combined wave that can show constructive or destructive interference patterns Correct answer.
  2. A phenomenon where waves always cancel each other out completely with no other outcome possible
  3. A term unrelated to wave behavior
  4. A phenomenon that occurs only with a single isolated wave, never multiple waves

Explanation

Interference is the superposition (combination) of two or more waves, resulting in a combined wave pattern that can show CONSTRUCTIVE interference (waves reinforcing, larger amplitude) or DESTRUCTIVE interference (waves canceling, smaller/zero amplitude), depending on their relative phase.

Question 39Waves Optics

What is 'Beugung' (diffraction) of waves?

  1. The bending or spreading of waves as they pass around obstacles or through small openings Correct answer.
  2. A phenomenon where waves always travel in perfectly straight lines with no spreading whatsoever
  3. A term unrelated to wave behavior
  4. A phenomenon exclusive to sound waves, never light

Explanation

Diffraction is the bending or spreading of waves as they encounter and pass around obstacles or through small openings (apertures), a characteristic wave phenomenon particularly noticeable when the opening/obstacle size is comparable to the wavelength.

Question 40Waves Optics

What is the correct meaning of 'Frequenz' (frequency) as a wave property?

  1. The number of complete oscillations or wave cycles occurring per unit of time, measured in Hertz (Hz) Correct answer.
  2. The distance between two successive wave crests
  3. A term unrelated to periodic motion or waves
  4. A quantity measured exclusively in meters

Explanation

Frequency is the number of complete oscillations or wave cycles occurring per unit of time (typically per second), measured in Hertz (Hz), where 1 Hz equals one cycle per second.

Question 41Waves Optics

What is the relationship between period (T) and frequency (f) of an oscillation?

  1. T = 1/f (period is the reciprocal of frequency) Correct answer.
  2. T = f (they are numerically identical in all cases)
  3. T = f² (period equals frequency squared)
  4. T and f have no mathematical relationship to each other

Explanation

Period (T, the time for one complete cycle) and frequency (f, cycles per unit time) are reciprocals of each other: T = 1/f (and equivalently, f = 1/T).

Question 42Waves Optics

What is 'Amplitude' as a wave/oscillation property?

  1. The maximum displacement of a wave or oscillating system from its equilibrium (rest) position Correct answer.
  2. The time required for one complete cycle
  3. A term unrelated to wave properties
  4. A quantity that is always identical for every type of wave regardless of energy

Explanation

Amplitude is the maximum displacement of a wave or oscillating system from its equilibrium (rest) position, directly related to the energy carried by the wave (greater amplitude generally means greater energy).

Question 43Waves Optics

What is the correct meaning of 'Streuung' (scattering) of light, relevant to explaining why the sky appears blue?

  1. The redirection of light in various directions when it interacts with particles or irregularities in a medium Correct answer.
  2. A phenomenon where light always travels through a medium completely unaffected
  3. A term unrelated to atmospheric optics
  4. A phenomenon that affects all wavelengths of light identically with no wavelength dependence

Explanation

Scattering is the redirection of light in various directions when it interacts with particles or irregularities in a medium (like gas molecules in the atmosphere); Rayleigh scattering specifically scatters shorter (blue) wavelengths more strongly than longer (red) wavelengths, explaining the sky's blue appearance.

Question 44Waves Optics

What is the correct meaning of 'Schallgeschwindigkeit' (speed of sound), and what factor most directly affects its value in a given medium?

  1. The speed at which sound waves propagate through a medium, which depends on the medium's properties (e.g., density, elasticity, temperature for gases) Correct answer.
  2. A universal constant identical in all media regardless of their physical properties
  3. A term unrelated to wave propagation
  4. A speed that is always faster in a vacuum than in any solid material

Explanation

The speed of sound is the speed at which sound waves propagate through a medium, which depends significantly on the medium's physical properties - generally faster in solids than liquids, and faster in liquids than gases, with temperature also affecting the speed in gases.

Question 45Waves Optics

What is the correct meaning of 'Lichtgeschwindigkeit' (speed of light) in a vacuum, a fundamental physical constant?

  1. Approximately 3×10⁸ m/s, the speed at which electromagnetic waves (including visible light) propagate in a vacuum Correct answer.
  2. Approximately 3×10⁸ km/s, a thousand times faster than the correct value
  3. A speed that varies significantly and unpredictably from day to day
  4. A speed that is slower in a vacuum than in glass or water

Explanation

The speed of light in a vacuum is approximately 3×10⁸ m/s (299,792,458 m/s precisely), a fundamental physical constant representing the maximum speed at which information or energy can travel.

Question 46Waves Optics

What is the correct meaning of the term 'Brechungsindex' (refractive index) of a medium?

  1. A measure of how much a medium bends (refracts) light, related to the ratio of light's speed in a vacuum to its speed in that medium Correct answer.
  2. A term unrelated to optical properties of materials
  3. A quantity that is always exactly 1 for every possible material
  4. A measure of a material's color with no connection to light bending

Explanation

The refractive index (Brechungsindex, n) is a measure of how much a medium bends (refracts) light, defined as the ratio of light's speed in a vacuum (c) to its speed in that specific medium (v): n = c/v.

Question 47Waves Optics

What is the correct meaning of 'Totalreflexion' (total internal reflection), an optics phenomenon relevant to fiber optic technology?

  1. A phenomenon where light traveling from a denser to a less dense medium, at an angle exceeding a critical angle, is completely reflected rather than refracted through the boundary Correct answer.
  2. A phenomenon where light is always partially transmitted regardless of angle
  3. A term unrelated to optics or fiber optic cables
  4. A phenomenon that occurs only when light travels from a less dense to a denser medium

Explanation

Total internal reflection occurs when light traveling from a DENSER to a LESS dense medium strikes the boundary at an angle exceeding the critical angle, resulting in complete reflection back into the denser medium rather than any refraction through the boundary - the principle enabling fiber optic cables to transmit light signals over long distances.

Question 48Modern Physics

What is the 'photoelektrischer Effekt' (photoelectric effect), significant for early quantum theory?

  1. The emission of electrons from a material's surface when light of sufficient frequency strikes it Correct answer.
  2. A process where electrons are emitted regardless of the light's frequency, only depending on intensity
  3. A term unrelated to light-matter interaction
  4. A phenomenon that only occurs with radio waves, never visible or ultraviolet light

Explanation

The photoelectric effect is the emission of electrons from a material's surface when light of sufficient FREQUENCY (above a material-specific threshold frequency) strikes it, a phenomenon that could not be explained by classical wave theory and was explained by Einstein using quantized light particles (photons), earning him the Nobel Prize.

Question 49Modern Physics

What is the formula relating a photon's energy to its frequency (Einstein's photon energy equation)?

  1. E = h × f Correct answer.
  2. E = h / f
  3. E = h + f
  4. E = h − f

Explanation

A photon's energy is calculated as E = h × f, where h is Planck's constant and f is the frequency of the light.

Question 50Modern Physics

What is 'Welle-Teilchen-Dualismus' (wave-particle duality), a foundational concept in quantum physics?

  1. The principle that particles like light and electrons exhibit both wave-like and particle-like properties depending on the experimental context Correct answer.
  2. A principle stating that particles are exclusively waves with no particle properties whatsoever
  3. A principle unrelated to quantum physics
  4. A concept that applies only to macroscopic objects, never subatomic particles

Explanation

Wave-particle duality is the foundational quantum physics principle that entities like light (photons) and electrons exhibit BOTH wave-like properties (interference, diffraction) and particle-like properties (discrete energy packets, localized detection), depending on the experimental context.