Physics 1010, Fall 2005 Name:
Exam #2 Signature:
Please provide one and only one answer for each question below.
1. An old slow car moves at a steady 10 km/hr down a straight highway, while
another car zooms past at a steady 120 km/hr. Which car has the greater net force on it?
(a) the slow car (b) the fast car (c) the net forces are the same (d) you can’t tell
2. Two people, one heavy and one light, are standing on ice. Assume there is no
friction between their feet and the ice. If the two people push off against one another, who
will experience the greater acceleration?
(a) the heavy person
(b) the light person
(c) their accelerations are the same
(d) it depends on who pushes hardest
3. A force can do work on a mass without the mass moving
(a) if the force is conservative.
(b) if the force is nonconservative.
(c) if only frictional forces are present.
(d) never.
4. If an object is moving at constant velocity, which of the following is false?
(a) The net force on the object is zero.
(b) Forces are doing work on the object.
(c) The object is not moving in a circle.
(d) All the forces acting on the object must be conservative.
5. When the instructor (JB) laid on a bed of nails and Ziggy broke a cinderblock
on his chest with a sledge hammer, JB was protected by;
(a) The inertia of the sledge hammer.
(b) The fact that he was lying on a bed of nails and not the floor.
(c) The cinderblock increased the stopping time for the hammer.
(d) The force broke the cinderblock, so there was no force left for JB’s chest.
