Which one of the following is not a unit? (Newton, Kilometer, Kelvin, Momentum)
Momentum
Using the standard physical meanings of the quantities t, x, v, and a, choose which of the following equations are dimensionally consistent.
x=v/2a
Not Consistent
which of the equations are dimensionally consistent?
v^2=2ax
Consistent
which of the equations are dimensionally consistent?
x=vt
Consistent
which of the equations are dimensionally consistent?
v=at^2/2
Not Consistent
For this example, let
ma and mb be masses
l1, l2, l3 and x be lengths
t1 and t2 be times
A mass density is defined as mass per volume, and a volume has a dimension of [L]3. Which of the following could be mass densities? (True or False)
ma/l1
l2
l3
True
which of the following could be mass densities?
m^2b/l1*l2
False
which of the following could be mass densities? (True or False)
ma
mb/l1
l2
False
which of the following could be mass densities (True or False)
ma/l^21
l^22
x
True
Rank the following values in order of increasing number of significant digits.
6.2x10^3
1.0375x10^9
300
300.
40,000.0
2: 6.2x10^3
4: 1.0375x10^9
1: 300
3: 300.
5: 40,000.0
Choose whether each of the following statements is true or false.
An object with a nonzero acceleration at some instant of time can have a velocity of zero at that instant.
True
Choose whether each of the following statements is true or false.
An object with a nonzero velocity can have an acceleration of zero.
True
Choose whether each of the following statements is true or false.
An object that is accelerating must have a nonzero average velocity.
False
If the airplane had double the acceleration and double the necessary takeoff speed, how long would the runway have to be?
Double the length
Half the length
Four times the length
Same length
Double the length
A baseball is thrown vertically upwards into the air (neglect air resistance) and returns to the starting point. (True or False)
The average speed is zero.
False
A baseball is thrown vertically upwards into the air (neglect air resistance) and returns to the starting point. (True or False)
The initial speed and final speed are equal.
True
A baseball is thrown vertically upwards into the air (neglect air resistance) and returns to the starting point. (True or False)
The initial velocity and final velocity are equal
False
A baseball is thrown vertically upwards into the air (neglect air resistance) and returns to the starting point. (True or False)
The average acceleration is zero.
False
A baseball is thrown vertically upwards into the air (neglect air resistance) and returns to the starting point. (True or False)
The average velocity is zero.
True
A baseball is thrown vertically upwards into the air (neglect air resistance) and returns to the starting point. (True or False)
The total displacement is zero.
True
Rank the vectors in the above diagram in order of increasing magnitude.
A ----> B / C <---- D \
1:A 2:B 3:D 4:C
Rank the vectors in the above diagram in order of increasing value of their x components.
A ----> B / C <---- D \
1:C 2:B 3:A 4:D
Rank the vectors in the above diagram in order of increasing value of their y components.
A ----> B / C <---- D \
1:D 2:C 3:A 4:B
The velocity vector V1 has a magnitude of 4.0 m/s and is directed along the +x-axis. The velocity vector V2 has a magnitude of 3.0 m/s. The sum of the two is V3 , so that V3= V1 + V2 (True or False)
The magnitude of V3 can be 8.0 m/s
False
The velocity vector V1 has a magnitude of 4.0 m/s and is directed along the +x-axis. The velocity vector V2 has a magnitude of 3.0 m/s. The sum of the two is V3 , so that V3= V1 + V2 (True or False)
The magnitude of V3 can be 0.0
False
The velocity vector V1 has a magnitude of 4.0 m/s and is directed along the +x-axis. The velocity vector V2 has a magnitude of 3.0 m/s. The sum of the two is V3 , so that V3= V1 + V2 (True or False)
The magnitude of V3 can be -4.0 m/s
False
The velocity vector V1 has a magnitude of 4.0 m/s and is directed along the +x-axis. The velocity vector V2 has a magnitude of 3.0 m/s. The sum of the two is V3 , so that V3= V1 + V2 (True or False)
The x-component of V3 can be 4.0 m/s
True
The velocity vector V1 has a magnitude of 4.0 m/s and is directed along the +x-axis. The velocity vector V2 has a magnitude of 3.0 m/s. The sum of the two is V3 , so that V3= V1 + V2 (True or False)
The magnitude of V3 can be 6.0 m/s
True
The velocity vector V1 has a magnitude of 4.0 m/s and is directed along the +x-axis. The velocity vector V2 has a magnitude of 3.0 m/s. The sum of the two is V3 , so that V3= V1 + V2 (True or False)
The magnitude of V3 can be 7.0 m/s
True
The plot shows the trajectory (height versus distance) of an object launched at an angle of =69.7 degrees with the horizontal and an initial speed . What is the magnitude of the acceleration of the object at the highest point of the trajectory?
gsin?
g
gc
g
What is the magnitude of the velocity of the object at the highest point of the trajectory?
0
Vocos?
Vo
Vosin?
Vocos?
Stones are thrown horizontally, with the same initial velocity, from the tops of two different buildings, A and B. The stone from building A lands 6 times as far from the base of the building as does the stone from building B. What is the ratio of buildin
36
Choose whether each of the following statements is true or false.
An object at rest has no forces acting on it.
False
Choose whether each of the following statements is true or false.
An object can be moving in one direction while the net force acting on it is in another direction.
True
Choose whether each of the following statements is true or false.
In order to move a massive crate sitting on the floor, the force you apply to the crate has to overcome the force of the crate pushing back on you.
False
Choose whether each of the following statements is true or false.
An object can be in motion and still have zero net force acting on it.
True
A truck is pulling a car. FT is the magnitude of the force that the truck exerts on the car FC is the magnitude of the force that the car exerts on the truck. Consider the following scenarios independently.The truck is slowing down on a horizontal surface
FT=FC>0
The truck is driving up a mountain with a constant velocity, neglecting friction.
FT>FC
FT<FC
FT=FC>0
FT=FC=0
FT=FC>0
The truck is coasting along with a constant velocity on a horizontal surface, neglecting friction.
FT>FC
FT<FC
FT=FC>0
FT=FC=0
FT=FC=0
You jump out of an airplane, and your parachute opens after a brief period of free fall. In order to slow your fall, the parachute must exert a force that is
equal to your weight.
less than your weight.
greater than your weight.
greater than your weight.
A cart of mass m can move without friction on an airtrack. Initially, it is at rest. Then, for a limited time t , it is pushed down the track with a constant force F. Which of the following statements are true?
While the cart is pushed, it has a constant
True
A cart of mass m can move without friction on an airtrack. Initially, it is at rest. Then, for a limited time t , it is pushed down the track with a constant force F. Which of the following statements are true.
You exert a larger force on the cart than th
False
A cart of mass m can move without friction on an airtrack. Initially, it is at rest. Then, for a limited time t , it is pushed down the track with a constant force F. Which of the following statements are true.
When you stop pushing, the cart will continu
True
A barrel (mass mLoad) is attached to a massless rope, which is attached to a hook (mass mHook), which is attached to the massless cable of a crane. The cable is accelerating up with an acceleration a. What is the tension of the rope?
mhook+mload*g-a
mload
mload
g+mload
a
What is the tension of the cable?
mhook+mload*g+a
mhook
g+mhook
a
mhook+mload*g-a
mhook*a
mhook*g-a
mhook(g+a)
mhook*g
mload
g+mhook
a
mhook+mload*g+a
Consider the system known as Atwood's Machine (two masses hanging over a pulley. Assume the two masses m1 and m2 are not equal. Suppose m1 and m2 are increased by the same multiplicative factor (in other words, each mass is multiplied by the same number).
The acceleration is unchanged.
Again, suppose m1 and m2 are increased by the same multiplicative factor. What happens to the tension in the rope?
The tension may increase, stay the same, or decrease, depending on the size of the multiplicative factor.
The tension decreases.
The tension
The tension increases.
Suppose m1 and m2 are increased by the same additive factor (in other words, each mass has the same amount of extra mass added to it). What happens to the acceleration of the system?
The acceleration is unchanged.
The acceleration decreases.
The accelerat
The acceleration decreases.
In the figure to the right, M2 has more mass than M1 and M1 has more mass than M3. The questions refer to the magnitudes of tensions and weights. There is friction between the horizontal plane and M2 (Mk not = 0). M2 is observed to travel at a constant sp
False
In the figure to the right, M2 has more mass than M1 and M1 has more mass than M3. The questions refer to the magnitudes of tensions and weights. There is friction between the horizontal plane and M2 (Mk not = 0). M2 is observed to travel at a constant sp
Equal to
In the figure to the right, M2 has more mass than M1 and M1 has more mass than M3. The questions refer to the magnitudes of tensions and weights. There is friction between the horizontal plane and M2 (Mk not = 0). M2 is observed to travel at a constant sp
True
In the figure to the right, M2 has more mass than M1 and M1 has more mass than M3. The questions refer to the magnitudes of tensions and weights. There is friction between the horizontal plane and M2 (Mk not = 0). M2 is observed to travel at a constant sp
Equal to
In the figure to the right, M2 has more mass than M1 and M1 has more mass than M3. The questions refer to the magnitudes of tensions and weights. There is friction between the horizontal plane and M2 (Mk not = 0). M2 is observed to travel at a constant sp
Equal to
In the figure to the right, M2 has more mass than M1 and M1 has more mass than M3. The questions refer to the magnitudes of tensions and weights. There is friction between the horizontal plane and M2 (Mk not = 0). M2 is observed to travel at a constant sp
Less than
A sled (mass 320 kg) is pulled across a stone floor with a coefficient of kinetic friction of 0.7. The rope that is used to pull it is at an angle a of 30 degrees with the horizontal. When the sled moves at a constant velocity (i.e., no acceleration), the
lower than the sled's weight.
Now you want to make the sled speed up as indicated. What does the magnitude of the required pulling force not depend on?
The current velocity of the sled
The coefficient of kinetic friction between the sled and the floor
The mass of the sled
The angle at
The current velocity of the sled
Two blocks A and B (mA>mB) are pushed for a certain distance along a frictionless surface. How does the magnitude of the work that A does on B compare to the magnitude of the work that B does on A?
Same (and not zero)
The magnitude of the work of B on A i
Same (and not zero)
How does the magnitude of the net work on A compare to the magnitude of the net work on B?
More net work on A
More net work on B
Same
More net work on A
How does the magnitude of the net work on A compare to the magnitude of the work of the hand on A?
Magnitude of the work by the hand on A is larger
Magnitude of the net work on A is larger
Same
Magnitude of the work by the hand on A is larger
A certain amount of work W is required to accelerate a motorcycle from rest to a speed v. How much work is required to accelerate the same motorcycle from v/3 up to a speed v?
W/3
W/4
W/10
8W/9
W/9
8W/9
Jogger A has a mass m and a speed v, jogger B has a mass m/3 and a speed 2v, jogger C has a mass 2m and a speed v/3, and jogger D has a mass 9m and a speed v/3. Rank the joggers in order of increasing kinetic energy. Indicate ties where appropriate.
1:C 2:A 2:D 4:B
A car accelerates from rest to a certain velocity in a certain time. Assume that there is no friction, and that the engine power is constant. Consider the following scenarios independently.
How long would it take to reach double the velocity (also from re
Four times the time.
How long would it take to reach the same velocity if the engine had twice the power?
Half the time.
Same time.
Double the time.
Four times the time.
Half the time.
A ball is thrown straight up into the air with an initial vertical velocity, v. It rises to a height, h. The graphs below are plots of energy as a function of height. Match each description to the correct graph.
C / D--- A \ B U E
The ball's gravitational
Graph C
A ball is thrown straight up into the air with an initial vertical velocity, v. It rises to a height, h. The graphs below are plots of energy as a function of height. Match each description to the correct graph.
C / D--- A \ B U E
The ball's total mechani
Graph D
A ball is thrown straight up into the air with an initial vertical velocity, v. It rises to a height, h. The graphs below are plots of energy as a function of height. Match each description to the correct graph.
C / D--- A \ B U E
The ball's kinetic energ
Graph A