Pre-Lecture Quiz 12
Study online at https://quizlet.com/_76w82b
1. Two identical cars are driving in opposite directions at the same speed. Their
kinetic energies have ____.
different magnitudes and opposite signs
the same magnitude, but opposite signs
different magnitudes, but the same sign
the same magnitude and sign: the same magnitude and sign.
The kinetic energy of a moving object is always positive, regardless of the direction
it is moving in, or the coordinate system used.
2. A motorcycle drives up a steeply inclined ramp. The work done on the
motorcycle by the Earth's gravitational force is ____.
zero
negative
positive: negative
When an object's displacement has a component in a direction opposite that of a
given force, that force does negative work on the object.
3. During a certain time interval, the net work done on an object is zero joules.
We can be certain that ____.
the object was at rest at the end of this interval
the object's final speed was the same as its initial speed
the object was at rest during this entire interval.: the object's final speed was the
same as its initial speed
When the net work done on an object is zero, there is no overall change in the
object's kinetic energy.
4. The amount of kinetic energy an object has depends on its mass and its
speed.
Rank the following sets of oranges and cantaloupes from least kinetic energy
to greatest kinetic energy. If two sets have the same amount of kinetic energy,
place one on top of the other.
(1) mass: m and speed: v; (2) total mass: 2 m and speed: 1/2 v; (3) mass: 4 m
and speed: 1/4 v; (4) total mass: 4 m and speed: v; (5) mass: 4 m and speed:
v: least KN: 3, 2, 1, 4 and 5 most KN
5. If the net work done on an object is positive, what can you conclude about
the object's motion? Assume the object is in the absence of any other forces
1/2
Study online at https://quizlet.com/_76w82b
1. Two identical cars are driving in opposite directions at the same speed. Their
kinetic energies have ____.
different magnitudes and opposite signs
the same magnitude, but opposite signs
different magnitudes, but the same sign
the same magnitude and sign: the same magnitude and sign.
The kinetic energy of a moving object is always positive, regardless of the direction
it is moving in, or the coordinate system used.
2. A motorcycle drives up a steeply inclined ramp. The work done on the
motorcycle by the Earth's gravitational force is ____.
zero
negative
positive: negative
When an object's displacement has a component in a direction opposite that of a
given force, that force does negative work on the object.
3. During a certain time interval, the net work done on an object is zero joules.
We can be certain that ____.
the object was at rest at the end of this interval
the object's final speed was the same as its initial speed
the object was at rest during this entire interval.: the object's final speed was the
same as its initial speed
When the net work done on an object is zero, there is no overall change in the
object's kinetic energy.
4. The amount of kinetic energy an object has depends on its mass and its
speed.
Rank the following sets of oranges and cantaloupes from least kinetic energy
to greatest kinetic energy. If two sets have the same amount of kinetic energy,
place one on top of the other.
(1) mass: m and speed: v; (2) total mass: 2 m and speed: 1/2 v; (3) mass: 4 m
and speed: 1/4 v; (4) total mass: 4 m and speed: v; (5) mass: 4 m and speed:
v: least KN: 3, 2, 1, 4 and 5 most KN
5. If the net work done on an object is positive, what can you conclude about
the object's motion? Assume the object is in the absence of any other forces
1/2
