Contents

Mechanics

Fluids

Waves & Sound

Light

Electricity & Magnetism

Rank the following distance vs. time graphs from highest to lowest according to average speed. Give the highest rank to the one with the highest average speed.

1____ 2____ 3____ Answer. Answer : _B_C_A The slope of the distance-time graph is the average speed. (TOC)

1____ 2____ 3____ 4____

Answer. Answer : A and B are the same (+10 m/s) C and D are the same (-10 m/s) Change in velocity is final velocity minus initial velocity. (TOC)

The four situations below show before and after pictures of a car's velocity. Rank these situations from highest to lowest in terms of the change in velocity.

Rank the following graphs from highest to lowest according to average acceleration.

1____ 2____ 3____ Answer. Answer : _B_A_C The slope of the velocity-time graph is the average acceleration. (TOC)

Rank the following graphs from highest to lowest according to acceleration.

1____ 2____ Answer. Answer : _A _B (TOC)

The two situations below show two heavy masses that are tied to a bar with light pieces of thread, and thread is also tied to the bottoms of the wieghts. If the thread on the left is pulled downward slowly and the thread on the right is pulled downward quickly, which of the bottom threads are more likely to break?

A__ B__ Both__ Neither__ Answer. Answer : B The inertia of the mass on the right will tend to keep it at rest. Quickly changing the state of motionof a large mass requires a large force. This large force will break the bottom thread. (TOC)

Two forces are acting on an object that is on a frictionless surface. Which object will have the greater acceleration?

A__ B__ Same__ Answer. Answer : B Acceleration = Net Force/Mass (TOC)

In each case the magnitude of the pushing force is the same. Rank the normal forces that the wall applies to the pusher from smallest to largest.

A__ B__ C__ Answer. Answer : B A C Normal force is the component perpendicular to the wall. (TOC)

The two situations below show rocks being thrown straight out off ofcliffs. The speeds and heights are given. Which rock would hit the water first?

A__ B__ Same__ Answer. Answer : Same The time for a projectile to fall does not depend on horizontal speed. (TOC)

The two situations below show rocks being thrown straight out off ofcliffs. The speeds, heights, and rock masses are given. Which rock would hit the water first?

A__ B__ Same__ Answer. Answer : B The time for a projectile to fall depends on height. (TOC)

The three situations below show rockets at the moment their engines are turned off. The rocketshave different speeds and different masses. Rank the rockets from highest to lowest on the maximum height they will attain.

1__ 2__ 3__ Answer. Answer : B, A, C Maximum height depends on initial velocity. (TOC)

The two situations below show rocks being thrown straight out off ofcliffs. The speeds, heights, and rock masses are given. Which rock is thrown with more momentum?

A__ B__ Same__ Answer. Answer : B Momentum is mass times velocity (TOC)

The two situations below show rocks being thrown straight out off ofcliffs. The speeds, heights, and rock masses are given. Which rock has more potential energy when it is thrown?

A__ B__ Same__ Answer. Answer : A PE = mgh (TOC)

The two situations below show rocks being thrown straight out off ofcliffs. The speeds, heights, and rock masses are given. Which rock has more kinetic energy when it is thrown?

A__ B__ Same__ Answer. Answer : B KE = (1/2)mv^2 (TOC)

The two situations below show balls rolling down incline planes. If the balls are the same mass, which ball will have more kinetic energy when it reaches the bottom?

A__ B__ Same__ Answer. Answer : B The Kinetic Energy comes from the Potential Energy (PE = mgh). (TOC)

The two situations below show rocks being thrown straight out off ofcliffs. The speeds, heights, and rock masses are given. Which rock has more total energy when it is first thrown?

A__ B__ Same__ Answer. Answer : A Total Energy = PE + KE (TOC)

The two situations below show boxes being slid different distances across identical surfaces. If the boxes have the same mass, which box will require more work to slide?

A__ B__ Same__ Answer. Answer : B Work = Fxd. (TOC)

The situation below shows a man holding a wooden bar with hooks at varying distances from his hands. If a heavy weight is hung from one of the hooks rank from highest to lowest difficulty for holding up the bar.

A__ B__ C__ D__ Answer. Answer : D, C, B, A Torque = Fxl. (TOC)

The situation below shows a central drive gear turning three other gears with varying radii. Rank the three gears from highest to lowest based on torque.

A__ B__ C__ Answer. Answer : C, A, B Torque is directly related to radius (T = F x l). (TOC)

The situation below shows a central drive gear turning three other gears with varying radii. Rank the three gears from highest to lowest based on angular speed.

A__ B__ C__ Answer. Answer : B, A, C Angular speed is inversly related to radius. (TOC)

Fluids

Shown below are identical containers containing different fluids. Metal blocks with equal volumes made from different metals aresuspended in the fluids. Which block will have the greater buoyant force?

A__ B__ Same__ Answer. Answer : Same The buoyant force is equal to the weight of the fluid displaced. (TOC)

Shown below are containers containing identical fluids. The bottom of each container is plugged with a cork. Which cork has the greater pressure?

A__ B__ Same__ Answer. Answer : A The pressure on a liquid = weight density x depth. (TOC)

Shown below are containers containing fluids with different specific heats. Equal amounts of thermal energy are added to each. Rank from highest to lowest based on their specific heats.

1__ 2__ 3__ Answer. Answer : C B A C = Q/(mT). (TOC)