Please write your homework neatly. Don't try to cram all the problems into the
minimum space. Show your work clearly, and useful diagrams are always appropriate
and may get extra points. You may work with others, but the work should be your
own. I expect numeric answers to have a reasonable number of significant figures
and proper units.
Note: WebAssign grades only on the answer; I will grade only (mostly) on the
method! Make your method clear.
1. Fill in the following table which summarizes the words that describe
types of collisions:
|
objects stick together?
|
momentum conserved?
|
KE conserved?
|
|
| (a) an elastic collision |
|||
| (b) a completely inelastic collision | |||
| (c) an inelastic collision |
(d) Which of the types of collisions above is likely to be most
common in actual collisions? Why?
2.A rock of mass 5.0 kg moves to the right at 8.0 m/s toward
a snowball of mass 35 kg moving to the left at 2.0 m/s. After the collision,
the rock emerges along with 5.0 kg of the snow moving to the right at 4.0 m/s.
(a) Find the velocity of the remaining snow.
(b) Is this an elastic collision? Justify your answer, no points for just a
Yes or No.
(c) If the collision occurs in 0.025 sec, find the average force on the rock.
3. Cummings et al., Ch. 10, p. 294, Problem 78
4. Cummings et al., Ch. 10, p. 294, Problem 88
5. Bicycle Pedal Arm The length of a bicycle pedal
arm is 0.152 m, and a downward force of 116 N is applied to the pedal by the
rider's foot. What is the magnitude of the torque about the pedal arm's pivot
point when the arm makes the following angles with the vertical?
(a) 30°
(b) 90°
(c) 180°
This page maintained by Anne G. Young. Last modified 30-Oct-2004 .