Physics Chapter 5 Review
A child moving at a constant velocity carries a 2N ice-cream cone 1m across a level surface. What is the net work done on the ice-cream cone?
0J
How much elastic potential energy is stored in a bungee cord with a spring constant of 10.0N/m when the cord is stretched 2.00m? a. 10.0J b. 20.0J c. 40.0J d. 400.J
20.0J
Ball "a" has triple the mass and speed of ball "b". What is the ration of the kinetic energy of ball "a" to ball "b"? a. 3 b. 6 c. 9 d. 27
27
How much power is required to lift a 2.0kg mass at a speed of 2.0m/s? a. 2.0W b. 4.0W c. 9.8W d. 39W
39W
What is the unit for energy?
J
What is the unit for work?
J
The main difference between kinetic and potential energy is that
KE involves motion and PE involves postition
What is the unit for force?
N
What is the unit for weight?
N
What are the units for a spring constant?
N/m
What is the unit for spring constant?
N/m
Which is not an equation for power in terms of work, displacement, time, force, and/or velocity? a. P=Fv b. P=Fv/t c. P=W/t d. P=F(d/t)
P=Fv/t
Net work done by a net force acting on an object is equal to what?
The change in kinetic energy of the object
Is this statement about mechanical energy true or false? Total energy is always conserved
True
True or false With friction, mechanical energy is not conserved
True
What is the unit for power?
W
Which equation expresses the work-kinetic energy theorem? a. MEi=MEf b. Wnet=PE c. (change in)W=KE W=(change in)KE
W=(change in)KE
The common formula for work is
W=Fd
In which of the following is mechanical energy most likely conserved? a. a feather falls from the sky b. a hockey player digs his skates into the ice c. a football flies through the air d. a skateboard rolls into the grass
a football flies through the air
Gravitational potential energy is measured in relation to a. a zero level b. kinetic energy c. mechanical energy d. total potential energy
a zero level
Gravitational potential energy is measured in relation to a. kinetic energy b. mechanical energy c. total potential energy d. a zero level
a zero level
If mechanical energy is conserved, the energy at any point can be in the form of a. kinetic energy b. gravitational potential energy c. elastic potential energy d. all of the above
all of the above
Which of the following energy forms is not involved in hitting a tennis ball? a. kinetic energy b. chemical potential energy c. gravitational potential energy d. elastic potential energy
chemical potential energy
In the formula for elastic potential energy, what is the "x"?
distance stretched
What is the energy stored in a compressed or stretched object like a spring or an elastic band?
elastic potential energy
Which form of energy is involved in weighing fruit on a spring scale?
elastic potential energy
What is the ability to do work?
energy
In the presence of what is non-mechanical energy no longer negligible and mechanical energy no longer conserved?
frictional force
What are the two types of potential energy?
gravitational and elastic
What is the energy stored in the gravitational fields of interacting bodies?
gravitational potential energy
What are the two types of energy?
kinetic and potential
Which form of energy is associated with an object in motion?
kinetic energy
Which of the following refers to the sum of kinetic energy and all forms of potential energy? a. total energy b. mechanical energy c. non-mechanical energy d. (change in) energy
mechanical energy
Is work done if a force is applied without motion?
no
Is work done if an object is in motion but no force is applied?
no
Friction converts kinetic energy to a. mechanical energy b. non-mechanical energy c. potential energy d. total energy
non-mechanical energy
Which form of energy is associated with an object due to its position?
potential energy
What is considering time taken to to work?
power
Which of the following is the rate at which work is done? a. power b. potential energy c. kinetic energy d. mechanical energy
power
Is kinetic energy a scaler or vector?
scaler
Is work a scaler or vector?
scaler
In the formula for elastic potential energy, what is the "k"?
spring constant
Mechanical energy of a system of objects is a. sum of KE and PEg b. sum of KE and all relevant forms of PE c. sum of KE and PEe d. sum of all forms of energy
sum of KE and all relevant forms of PE
Work is done when a. the displacement is zero b. the displacement is not zero c. the force is zero d. the force and displacement are perpendicular
the displacement is zero
A more powerful motor can do a. more work in a longer time interval b. the same work in a shorter time interval c. less work in a longer time interval
the same work in a shorter time interval
What is done anytime a force is applied through a displacement?
work