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Question 1General Physics Fundamentals

A ball is dropped from rest and falls freely near Earth's surface. Ignoring air resistance, how far has it fallen after 3.0 s?

  1. 9.8 m
  2. 44 m Correct answer.
  3. 15 m
  4. 30 m

Explanation

For free fall from rest, distance equals one-half the gravitational acceleration times the square of the time: (1/2)(9.8 m/s²)(3.0 s)². This gives about 44 m. The other values come from misapplying the formula.

Question 2General Physics Fundamentals

Which quantity is a scalar?

  1. Displacement
  2. Speed Correct answer.
  3. Velocity
  4. Acceleration

Explanation

A scalar has magnitude only, while a vector has both magnitude and direction. Speed describes how fast something moves without specifying a direction, so it is a scalar. Velocity, displacement, and acceleration all include directional information.

Question 3General Physics Fundamentals

A 10 kg crate rests on a horizontal floor. What is the normal force the floor exerts on the crate?

  1. 0 N
  2. 98 N Correct answer.
  3. 10 N
  4. 49 N

Explanation

With no vertical acceleration, the normal force balances the crate's weight. Weight equals mass times gravitational acceleration, 10 kg × 9.8 m/s², which is 98 N.

Question 4General Physics Fundamentals

A wave has a frequency of 50 Hz and a wavelength of 4.0 m. What is its speed?

  1. 200 m/s Correct answer.
  2. 54 m/s
  3. 12.5 m/s
  4. 0.08 m/s

Explanation

Wave speed equals frequency multiplied by wavelength. Multiplying 50 Hz by 4.0 m gives 200 m/s. This relation holds for any periodic wave.

Question 5General Physics Fundamentals

Which statement describes the direction of heat flow between two objects in thermal contact?

  1. From the object with more thermal energy to the one with less
  2. From the larger object to the smaller object
  3. From the object at higher temperature to the one at lower temperature Correct answer.
  4. From the object with greater mass to the one with less mass

Explanation

Heat is energy transferred because of a temperature difference, and it flows spontaneously from higher to lower temperature. Total thermal energy and object size do not determine the direction. The flow continues until temperatures equalize.

Question 6General Physics Fundamentals

A 2.0 kg object moves in a straight line at a constant 3.0 m/s. What is its kinetic energy?

  1. 6.0 J
  2. 9.0 J Correct answer.
  3. 3.0 J
  4. 18 J

Explanation

Kinetic energy equals one-half the mass times the square of the speed. Computing (1/2)(2.0 kg)(3.0 m/s)² gives 9.0 J. Note that doubling the speed would quadruple this value.

Question 7General Physics Fundamentals

A converging lens forms a real image of a distant object. Where is the image located?

  1. At the focal point Correct answer.
  2. At twice the focal length
  3. At the center of curvature
  4. At the lens surface

Explanation

Rays from a very distant object arrive nearly parallel to the principal axis. A converging lens focuses parallel rays to the focal point, so the image forms essentially at the focal length.

Question 8General Physics Fundamentals

Two identical resistors of 6.0 Ω each are connected in parallel. What is the equivalent resistance?

  1. 3.0 Ω Correct answer.
  2. 6.0 Ω
  3. 0.33 Ω
  4. 12 Ω

Explanation

For two equal resistors in parallel, the equivalent resistance is half of one resistor's value. Thus 6.0 Ω divided by 2 gives 3.0 Ω. In general, parallel combinations always yield a resistance smaller than the smallest branch.

Question 9General Physics Fundamentals

A block slides down a frictionless incline of height 2.0 m. Taking g as 9.8 m/s², what is its speed at the bottom if it starts from rest?

  1. 19.6 m/s
  2. 9.8 m/s
  3. 4.4 m/s
  4. 6.3 m/s Correct answer.

Explanation

Conservation of energy gives one-half v² equal to g times height, since mass cancels. Solving for v gives the square root of 2 × 9.8 × 2.0, about 6.3 m/s. The incline angle affects travel time but not the final speed.

Question 10General Physics Fundamentals

A car traveling at 20 m/s brakes uniformly and stops in 4.0 s. What is the magnitude of its deceleration?

  1. 2.5 m/s²
  2. 5.0 m/s² Correct answer.
  3. 0.20 m/s²
  4. 80 m/s²

Explanation

Acceleration equals the change in velocity divided by the time interval. The change is 20 m/s over 4.0 s, giving 5.0 m/s². The negative sign would indicate direction opposite to motion.

Question 11General Physics Fundamentals

A 4.0 kg block is pushed across a rough floor by a horizontal force of 30 N. If the kinetic friction force is 10 N, what is the block's acceleration?

  1. 10 m/s²
  2. 5.0 m/s² Correct answer.
  3. 7.5 m/s²
  4. 2.5 m/s²

Explanation

Newton's second law uses the net force, which is the applied force minus friction: 30 N − 10 N = 20 N. Dividing by the 4.0 kg mass gives 5.0 m/s². Friction must be subtracted before dividing by mass.

Question 12General Physics Fundamentals

A 0.50 kg ball moving at 8.0 m/s strikes a wall and rebounds along the same line at 6.0 m/s. What is the magnitude of the impulse delivered to the ball?

  1. 14 N·s
  2. 4.0 N·s
  3. 7.0 N·s Correct answer.
  4. 1.0 N·s

Explanation

Impulse equals the change in momentum, and reversing direction makes the velocity change 8.0 + 6.0 = 14 m/s in magnitude. Multiplying by 0.50 kg gives 7.0 N·s. Treating the reversed velocity as negative is essential here.

Question 13General Physics Fundamentals

Two point charges are separated by a fixed distance. If the distance between them is doubled, the magnitude of the electrostatic force becomes

  1. four times as large
  2. one quarter as large Correct answer.
  3. twice as large
  4. half as large

Explanation

Coulomb's law states that force is inversely proportional to the square of the separation. Doubling the distance multiplies the force by one over two squared, which is one quarter. The inverse-square dependence is the key feature.

Question 14General Physics Fundamentals

An ideal gas in a rigid sealed container is heated so that its absolute temperature doubles. What happens to its pressure?

  1. It doubles Correct answer.
  2. It quadruples
  3. It stays the same
  4. It halves

Explanation

For a fixed amount of gas at constant volume, pressure is directly proportional to absolute temperature. Doubling the Kelvin temperature therefore doubles the pressure. A rigid container means volume cannot change.

Question 15General Physics Fundamentals

A simple pendulum has a period of 2.0 s on Earth. If it is taken to a planet where the gravitational acceleration is one quarter of Earth's, what is its new period?

  1. 8.0 s
  2. 0.50 s
  3. 4.0 s Correct answer.
  4. 1.0 s

Explanation

The period of a simple pendulum is proportional to the square root of length divided by gravitational acceleration. Reducing g to one quarter multiplies the period by the square root of four, which is two. The new period is therefore 4.0 s.

Question 16General Physics Fundamentals

A sound wave passes from air into water, where its speed is greater. What happens to its frequency?

  1. It becomes zero
  2. It increases
  3. It decreases
  4. It stays the same Correct answer.

Explanation

Frequency is set by the source and does not change when a wave crosses into a new medium. What changes is the wavelength, which adjusts so that speed equals frequency times wavelength. This is why voices sound the same in pitch but behave differently underwater.

Question 17General Physics Fundamentals

A 2.0 kg mass moving at 3.0 m/s collides with a stationary 1.0 kg mass and they stick together. What is their common velocity after the collision?

  1. 3.0 m/s
  2. 2.0 m/s Correct answer.
  3. 1.0 m/s
  4. 1.5 m/s

Explanation

In a perfectly inelastic collision, total momentum is conserved. Initial momentum is 2.0 kg × 3.0 m/s = 6.0 kg·m/s, and the combined mass is 3.0 kg, giving 2.0 m/s. Kinetic energy is not conserved in such a collision.

Question 18General Physics Fundamentals

An object is placed 30 cm from a converging lens of focal length 10 cm. Where does the image form?

  1. 10 cm on the far side
  2. 30 cm on the far side
  3. 15 cm on the same side as the object Correct answer.
  4. 20 cm on the far side

Explanation

The thin-lens equation gives 1/f = 1/do + 1/di, so 1/di = 1/10 − 1/30 = 1/15. The image distance is therefore 15 cm, and a positive value places a real image on the far side.

Question 19General Physics Fundamentals

A wire carries a steady current of 2.0 A for 30 s. How much charge passes a point in the wire?

  1. 2.0 C
  2. 15 C
  3. 0.067 C
  4. 60 C Correct answer.

Explanation

Current is the rate of charge flow, so charge equals current multiplied by time. Multiplying 2.0 A by 30 s gives 60 C. This follows directly from the definition of the ampere as one coulomb per second.

Question 20General Physics Fundamentals

A block of wood floats in water with part of its volume submerged. Which statement explains why it floats?

  1. The wood repels water molecules
  2. The wood is more dense than water
  3. The wood is less dense than water Correct answer.
  4. The wood has no weight in water

Explanation

An object floats when it can displace a weight of fluid equal to its own weight before becoming fully submerged. This happens when the object's average density is less than the fluid's density. A denser object would sink because it cannot displace enough fluid.

Question 21General Physics Fundamentals

An electron is accelerated from rest through a potential difference of 100 V. What is the magnitude of the work done on it?

  1. 100 J
  2. 9.1 × 10⁻³¹ J
  3. 1.6 × 10⁻¹⁷ J Correct answer.
  4. 1.6 × 10⁻²¹ J

Explanation

The work done on a charge moving through a potential difference equals charge times voltage. Using the elementary charge 1.6 × 10⁻¹⁹ C times 100 V gives 1.6 × 10⁻¹⁷ J. This energy appears as the electron's kinetic energy.

Question 22General Physics Fundamentals

A projectile is launched at an angle with an initial horizontal velocity component of 12 m/s and no air resistance. What is its horizontal velocity 2.0 s after launch?

  1. 24 m/s
  2. 20 m/s
  3. 0 m/s
  4. 12 m/s Correct answer.

Explanation

With no air resistance, no horizontal force acts on the projectile, so its horizontal velocity stays constant. The vertical velocity changes under gravity, but the horizontal component remains 12 m/s. The two components are independent.

Question 23General Physics Fundamentals

A gas absorbs 500 J of heat and does 200 J of work on its surroundings. What is the change in its internal energy?

  1. −300 J
  2. 300 J Correct answer.
  3. 700 J
  4. 500 J

Explanation

The first law of thermodynamics gives ΔU = Q − W when W is work done by the gas. Substituting 500 J − 200 J yields an increase of 300 J. Heat added raises internal energy while work done by the gas lowers it.

Question 24General Physics Fundamentals

A 0.20 kg mass on a spring with constant 80 N/m oscillates horizontally. What is the angular frequency of the motion?

  1. 0.050 rad/s
  2. 2.0 rad/s
  3. 20 rad/s Correct answer.
  4. 400 rad/s

Explanation

Angular frequency for a mass-spring system equals the square root of k divided by m. Dividing 80 N/m by 0.20 kg gives 400, and its square root is 20 rad/s. Mass and stiffness together set the frequency, not the amplitude.

Question 25General Physics Fundamentals

A parallel-plate capacitor is connected to a battery, fully charged, then disconnected. If the plate separation is then doubled, what happens to the stored energy?

  1. It stays the same
  2. It doubles Correct answer.
  3. It is halved
  4. It quadruples

Explanation

After disconnection the charge stays fixed, so energy is best written as Q²/(2C). Doubling the separation halves the capacitance, so the stored energy doubles. Because charge is trapped, the battery cannot supply or absorb energy during the change.

Question 26General Physics Fundamentals

A quantity that has magnitude but no direction is best described as which type of quantity?

  1. Scalar Correct answer.
  2. Tensor
  3. Vector
  4. Resultant

Explanation

A scalar is fully specified by a magnitude alone, such as mass, time, or temperature. Vectors require both magnitude and direction, which is the defining distinction.

Question 27General Physics Fundamentals

A body moves along a straight line with constant acceleration. Which statement about its velocity and acceleration is necessarily true?

  1. The acceleration changes at a constant rate.
  2. The velocity remains constant while the acceleration is nonzero.
  3. The velocity changes by equal amounts in equal time intervals. Correct answer.
  4. The velocity is zero whenever the acceleration is nonzero.

Explanation

Constant acceleration means the rate of change of velocity is fixed, so velocity changes by the same amount each second. This is the definition of uniform acceleration.

Question 28General Physics Fundamentals

A solid cube of uniform density is cut in half, and one half is kept. How does the density of the remaining half compare with that of the original cube?

  1. It is the same as before. Correct answer.
  2. It is twice as large.
  3. It is one half as large.
  4. It depends on which half is kept.

Explanation

Density is an intensive property determined by the material, not by the amount present. Halving both mass and volume leaves the ratio of mass to volume unchanged.

Question 29General Physics Fundamentals

In a transverse wave, the particles of the medium oscillate in which direction relative to the wave's direction of travel?

  1. At a fixed 45-degree angle to the direction of travel
  2. Parallel to the direction of travel
  3. Perpendicular to the direction of travel Correct answer.
  4. Along circular paths around the direction of travel

Explanation

By definition, transverse waves displace the medium perpendicular to the propagation direction, as in a wave on a string. Longitudinal waves displace the medium parallel to propagation.

Question 30General Physics Fundamentals

A force of 12 N acts on a 3.0 kg object that is free to move on a frictionless surface. What is the magnitude of the object's acceleration?

  1. 36 m/s²
  2. 9.0 m/s²
  3. 0.25 m/s²
  4. 4.0 m/s² Correct answer.

Explanation

Newton's second law gives a = F/m. Dividing 12 N by 3.0 kg yields 4.0 m/s².

Question 31General Physics Fundamentals

A uniform horizontal beam is supported at its two ends. A load is placed at the exact center of the beam. How does the upward support force at each end compare with the load's weight?

  1. Each support force equals the full load's weight.
  2. Each support force equals half the load's weight. Correct answer.
  3. Each support force equals one quarter of the load's weight.
  4. Each support force equals twice the load's weight.

Explanation

By symmetry the two supports share the load equally, and vertical equilibrium requires the two upward forces to sum to the weight. Each support therefore carries half the weight.

Question 32General Physics Fundamentals

Two identical waves of the same frequency travel in the same direction along a string with a phase difference of 180 degrees. What is the amplitude of the resulting wave?

  1. Twice the amplitude of one wave
  2. Zero Correct answer.
  3. Equal to the amplitude of one wave
  4. Half the amplitude of one wave

Explanation

Waves that are exactly out of phase interfere destructively, and equal amplitudes cancel completely. The superposition of the two displacements gives zero at every point.

Question 33General Physics Fundamentals

A container holds 2.0 moles of an ideal gas at 300 K. Taking the universal gas constant as 8.3 J/(mol·K), what is the pressure if the volume is 0.050 m³?

  1. About 1.0×10⁵ Pa Correct answer.
  2. About 2.0×10⁵ Pa
  3. About 5.0×10⁴ Pa
  4. About 2.5×10⁴ Pa

Explanation

The ideal gas law gives P = nRT/V. Substituting 2.0 mol, 8.3 J/(mol·K), and 300 K over 0.050 m³ yields roughly 1.0×10⁵ Pa.

Question 34General Physics Fundamentals

A current-carrying wire is placed in a uniform magnetic field so that the wire lies parallel to the field lines. What is the magnitude of the magnetic force on the wire?

  1. Equal to the current times the field strength
  2. Maximum possible for that current and length
  3. Zero Correct answer.
  4. Proportional to the cosine of the angle between wire and field

Explanation

The magnetic force on a straight wire is proportional to the sine of the angle between the wire and the field. When the wire is parallel to the field the sine is zero, so the force vanishes.

Question 35General Physics Fundamentals

An object is placed between a converging lens and its focal point. Which type of image is produced?

  1. A virtual, upright, magnified image Correct answer.
  2. A real, inverted, diminished image
  3. A virtual, inverted, same-size image
  4. A real, upright, diminished image

Explanation

When the object distance is less than the focal length of a converging lens, the rays diverge after the lens and the image is virtual, upright, and enlarged. This is the principle of a magnifying glass.

Question 36General Physics Fundamentals

A radioactive sample has a half-life of 8.0 days. What fraction of the original nuclei remains after 24 days?

  1. One third
  2. One eighth Correct answer.
  3. One quarter
  4. One sixteenth

Explanation

Twenty-four days spans three half-lives because 24 divided by 8.0 equals 3. Each half-life halves the remaining amount, so the fraction left is (1/2)³ = 1/8.

Question 37General Physics Fundamentals

A 5.0 kg crate is lifted vertically at a constant speed through a height of 2.0 m. Taking g as 9.8 m/s², how much work does the lifting force do on the crate?

  1. 98 J Correct answer.
  2. 10 J
  3. 49 J
  4. 0 J

Explanation

At constant speed the lifting force equals the weight, mg, and work is force times displacement in the direction of the force. Thus W = (5.0)(9.8)(2.0) = 98 J.

Question 38General Physics Fundamentals

A charged particle enters a region of uniform magnetic field with its velocity perpendicular to the field. Which description best characterizes its subsequent motion?

  1. Uniform circular motion at constant speed Correct answer.
  2. Straight-line motion parallel to the field at constant speed
  3. Straight-line motion with constant acceleration along the field
  4. A parabolic path with increasing speed

Explanation

The magnetic force is always perpendicular to the velocity, so it changes direction but not speed. A constant-magnitude force perpendicular to motion produces uniform circular motion.

Question 39General Physics Fundamentals

An ideal gas undergoes an adiabatic expansion. Which statement correctly describes the energy transfers and temperature change?

  1. Heat flows into the gas, and its temperature rises.
  2. No heat is exchanged, no work is done, and its temperature is unchanged.
  3. No heat is exchanged, the gas does work, and its temperature falls. Correct answer.
  4. Heat flows out of the gas, and its temperature rises.

Explanation

Adiabatic means no heat exchange with the surroundings. In an expansion the gas does positive work, so by the first law its internal energy decreases and the temperature drops.

Question 40General Physics Fundamentals

A block of mass m rests on a rough horizontal surface with coefficient of static friction μ. A horizontal force is applied and gradually increased. Just before the block begins to slide, what is the magnitude of the friction force?

  1. μmg Correct answer.
  2. Greater than μmg
  3. Equal to the applied force minus mg
  4. Zero

Explanation

The normal force on a horizontal surface equals mg, so the maximum static friction is μmg. At the threshold of slipping, the static friction has reached this limiting value.

Question 41Classical Mechanics

A particle moves along a straight line with constant acceleration. Which statement about its velocity-versus-time graph is true?

  1. It is a parabola opening upward.
  2. It is a straight line whose slope equals the acceleration. Correct answer.
  3. It is a straight line whose slope equals the displacement.
  4. It is a horizontal line at constant velocity.

Explanation

For constant acceleration, velocity changes linearly with time, v = v0 + at, so the graph is a straight line with slope a. The area under the line gives displacement, not the slope.

Question 42Classical Mechanics

A projectile is launched over level ground. Ignoring air resistance, at the highest point of its trajectory which quantity is zero?

  1. The horizontal component of velocity
  2. The acceleration
  3. The speed
  4. The vertical component of velocity Correct answer.

Explanation

At the apex the vertical velocity component passes through zero as it reverses direction, while the horizontal component and the downward acceleration g remain unchanged. The speed is therefore equal to the horizontal component, not zero.

Question 43Classical Mechanics

A block slides down a frictionless incline of angle θ. What is its acceleration along the incline?

  1. g cos θ
  2. g sin θ Correct answer.
  3. g
  4. g tan θ

Explanation

The only force along the incline is the component of gravity, mg sin θ, so the acceleration is g sin θ. The normal force balances the perpendicular component mg cos θ and contributes nothing along the slope.

Question 44Classical Mechanics

Two forces act on a particle and the net force is zero. What can be concluded about the particle's motion?

  1. Its velocity is constant. Correct answer.
  2. Its speed must be zero.
  3. It must be at rest.
  4. Its acceleration is increasing.

Explanation

By Newton's first law, zero net force means zero acceleration, so velocity is constant in both magnitude and direction. Constant velocity may be nonzero, so rest is only a special case.

Question 45Classical Mechanics

A spring obeys Hooke's law with constant k. If it is stretched so that its extension doubles, the stored elastic potential energy becomes

  1. unchanged
  2. half as large
  3. four times as large Correct answer.
  4. twice as large

Explanation

Elastic potential energy for a Hooke spring is U = ½kx², which scales with the square of the extension. Doubling x therefore multiplies the energy by four.

Question 46Classical Mechanics

A system of particles moves without external forces. Which quantity is necessarily conserved?

  1. Total kinetic energy
  2. Total linear momentum Correct answer.
  3. Total angular momentum about every moving point
  4. Total potential energy

Explanation

With zero net external force, total linear momentum of the system is conserved. Kinetic and potential energy need not be conserved unless the internal forces are conservative and no energy is dissipated.

Question 47Classical Mechanics

A rigid body rotates about a fixed axis with constant angular velocity. Which point on the body has the greatest linear speed?

  1. The center of mass
  2. The point closest to the axis
  3. All points have equal linear speed
  4. The point farthest from the axis Correct answer.

Explanation

Linear speed for rotation about a fixed axis is v = ωr, so for fixed ω the speed grows with distance r from the axis. The farthest point therefore moves fastest.

Question 48Classical Mechanics

A simple pendulum of length L has small-amplitude oscillations. Its period is independent of which quantity?

  1. The mass of the bob Correct answer.
  2. The acceleration due to gravity
  3. The amplitude for small swings
  4. The length of the string

Explanation

For small oscillations the period is T = 2π√(L/g), which contains no mass term. Mass cancels because both the restoring force and inertia scale with it.

Question 49Classical Mechanics

A 2 kg object moving at 3 m/s collides head-on with a stationary 4 kg object and they stick together. What is the common velocity after the collision?

  1. 1 m/s Correct answer.
  2. 1.5 m/s
  3. 3 m/s
  4. 2 m/s

Explanation

Momentum conservation for a perfectly inelastic collision gives (2)(3) = (2+4)v, so v = 6/6 = 1 m/s. Kinetic energy is not conserved in this collision.

Question 50Classical Mechanics

A block is pushed up a rough incline and then released. While it slides back down at constant speed, the magnitude of kinetic friction equals

  1. μ mg sin θ
  2. mg
  3. mg cos θ
  4. mg sin θ Correct answer.

Explanation

Constant speed means zero net force along the incline, so friction balances the downslope gravity component mg sin θ. The coefficient μ is not needed once the motion is known to be at constant speed.