Honors Physics Midterm (multiple choice)

An object is released from rest on a planet that has no atmosphere. The object falls freely for 3.0 meters in the first second. What is the magnitude of the acceleration due to gravity on the planet?

a) 1.5m/s^2

b) 3.0m/s^2

c) 6.0m/s^2

d) 10.0m/s^2

C

the magnitude of the velocity of an object is increasing when...

it's position/distance increases gradually over time

the acceleration of an object is zero when...

its position/distance either remains the same or consistently increases over time (there is no change in velocity)

Two objects, X and Y, accelerate from rest with the same constant acceleration. Object X accelerates for twice the time as object Y. Which of the following is true of these objects at the end of their respective periods of acceleration?

a) object X is moving at the same speed as object Y

b) object X is moving four times faster than object Y

c) object X has traveled the same distance as object Y

d) object X has traveled twice as far as object Y

e) object X has traveled four times as far as object Y

E

Starting from rest, a vehicle accelerates on a straight level road at the rate of 4.0m/s^2 for 5.0s. What is the speed of the vehicle at the end of this time interval?

a) 1.3m/s

b) 10m/s

c) 20m/s

d) 80m/s

e) 100m/s

C

Starting from rest, a vehicle accelerates on a straight level road at the rate of 4.0m/s^2 for 5.0s. What is the total distance the vehicle travels during this time interval?

a) 10m

b) 20m

c) 25m

d) 40m

e) 50m

E

If air resistance is negligible, the speed of a 2kg sphere that falls from rest through a vertical displacement of 0.2m is most nearly...

a) 1m/s

b) 2m/s

c) 3m/s

d) 4m/s

e) 5m/s

B

An object of unknown mass is initially at rest and dropped from a height (h). It reaches the ground with a velocity (v1). The same object is then raised again to the same height but this time is thrown downward with velocity v1. It now reaches the ground with a new velocity v2. How is v2 related to v1?

a) v2 = v1/2

b) v2 = v1

c) v2 = 2v1

d) v2 = (√2)v1

e) v2= 4v1

D

In the absence of air friction, an object dropped near the surface of the Earth experiences a constant acceleration of about 9.8m/s^2. This means that the...

a) speed of the object increases 9.8m/s during each second

b) speed of the object as it falls is 9.8m

c) object falls 9.8m during each second

d) object falls 9.8m during the first second only

e) derivative of the distance with respect to time for the object is 9.8m/s^2

A

What is the weight of a 5kg rock on earth?

a) 5kg

b) 49kg

c) 9.8N

d) 5N

e) 49N

E

In which direction does the normal force always act?

a) up

b) perpendicular to a surface

c) opposite of the gravitational force

d) North

e) parallel to a surface face

B

What is the following statement sometimes called?

"An object in a uniform state of motion will remain in a uniform state of motion unless acted upon by an external, unbalanced force."

a) The Law of Force

b) Newton's Fourth Law

c) The Law of Inertia

d) The Meaning of Life

e) Newton's Second Law

C

The coefficient of kinetic friction is...

a) the tendency of two surfaces to stick together as they slide across each other

b) the force of friction acting between a stationary object and a surface

c) the tendency of two surfaces to stick together when stationary

d) The force of friction acting between a moving object and a surface

e) the ratio of frictional force to mass

A

What subscript is never written but always seems to be present next to the F in F=ma?

a) final

b) initial

c) total

d) frictional

e) normal

C

What is the first step in solving any force problem?

a) free body diagram

b) force body diagram

c) force balance diagram

d) free balanced drawing

e) force balanced direction

A

weight is an example of a...

a) contact force

b) fake force

c) remote or field force

d) scale force

e) mass

C

What are the two types of coefficients of friction and which of the following is true regarding their relative size?

a) Static and Kinetic. Kinetic is usually larger.

b) Stoic and Kinesthetic. Kinesthetic is usually smaller.

c) Seismic and Kinetic. Seismic is always greater.

d) Kinetic and Static. Static is almost always greater.

e) Kinesthetic and Stereo. Stereo is usually larger.

D

When you are riding a scale in an elevator, the reading can change. What does the scale reading give you?

a) weight

b) mass

c) frictional force

d) total force

e) normal force

E

You weigh 125lbs. You are in an elevator standing on a scale. Assuming the scale is properly calibrated, what might the elevator be doing if the scale reads 135lbs?

a) it is at rest

b) it is moving downward and slowing

c) it is moving upward and slowing

d) it is moving upward and slowing

e) it is accelerating downward

B

What can work do to a mechanical energy?

a) it can increase gravitational potential energy

b) it can increase Kinetic Energy

c) it can decrease Kinetic Energy

d) it can decrease gravitational potential energy

e) it can do all of the above

E

Energy is a conserved quantity. What does that mean?

a) Energy is saved for future use in all systems.

b) Energy cannot be created or destroyed, it can only change form.

c) When you do outside work on a system, you do not change the total energy.

d) Energy voted for Mitt Romney in the 2012 election

e) Lost energy is mostly dissipated as heat

B

A spring is compressed 10cm from equilibrium. It has stored X Joules of energy at that point. It is then compressed 10cm further. How much energy has it stored?

a) X joules

b) 2X joules

c) more than 2X joules

d) less than 2x joules

e) between X and 2x joules

C

A monkey swings back and forth on a vine. At what point does it have the greatest amount of kinetic energy?

a) at the lowest point

b) at the highest point

c) half way between the lowest and highest point

d) impossible to tell from the description

e) closer to the lowest point that the highest

A

How much work is required to lift a 3kg puppy from the floor to a counter top 88cm above the floor?

a) 0 Joules

b) 264 Joules

c) 25.87 Joules

d) 2587 Joules

e) 2.64 Joules

C

A Joule is equivalent to...

a) (kg*m)/s

b) (kg*m)/(s^2)

c) kg/(m*s^2)

d) (kg^2*m)/(s^2)

e) (kg*m^2)/(s^2)

E

Gravitational potential energy is best thought of as energy of...

a) motion

b) heat

c) speed

d) position

e) compression

D

How much work is done in holding a 1kg box for 2 seconds?

a) 2J

b) 9.8J

c) 19.6J

d) 4.9J

e) 0J

E

Energy is always conserved, but mechanical energy is not. Why?

a) some energy is turned into gravitational potential energy

b) some energy is turned into heat

c) some energy is turned into kinetic energy

d) all energy is turned into either gravitational potential or kinetic energy

e) all energy is turned into heat

B

What are the three types of mechanical energy we have discussed?

a) Kinetic, Gravitational Potential, and Heat

b) Heat, Spring Potential, and Kinetic

c) Heat, Spring Potential, and Gravitational Potential

d) Kinetic, Spring Potential, and Gravitational Potential

e) Work, Heat, and Kinetic

D

Newton described momentum as...

a) The velocity of an object

b) the kinetic energy of an object

c) the quantity of motion possessed by an object

d) the force an object can exert on other objects

e) the ability of an object to transfer energy

C

A 2kg ball moves along at 4m/s. What is the momentum of the ball?

a) 8N

b) 2N

c) .5N

d) 8 (kg x m)/s

e) 2 (kg x m)/s

D

Which quantities are conserved in a totally inelastic collision?

a) momentum and energy

b) momentum, energy, and force

c) just momentum

d) just energy

e) just force

C

Which quantities are conserved in a totally elastic collision?

a) momentum and energy

b) momentum, energy, and force

c) just momentum

d) just energy

e) just force

A

Which quantities are conserved in an explosion?

a) momentum and energy

b) momentum, energy, and force

c) just momentum

d) just energy

e) just force

C

A 4kg ball moves along at 2m/s and a 2kg ball moves along at 4m/s.

a) both have the same momentum

b) both have the same kinetic energy

c) both have the same momentum and kinetic energy

d) neither has kinetic energy

e) neither has momentum

A

Which is a conserved quantity in nature?

a) momentum

b) energy

c) momentum and energy

d) neither momentum nor energy

e) forces

C

In what type of collision is some mechanical energy converted into heat energy?

a) inelastic

b) elastic

c) catastrophic

d) elastic and inelastic

e) heat is not produced in any collision

A

In what type of collision is no mechanical energy converted into heat energy?

a) inelastic

b) elastic

c) catastrophic

d) elastic and inelastic

e) heat is not produced in any collision

B

If two objects collide and stick together, the collision could be described as...

a) catastrophic

b) Gelastinous

c) elastic

d) inelastic

e) semi-elastic

D