Transcript p total initial - Cloudfront.net

PHYSICS
Monday, 12/15/08
PHYSICS
If you do the same old things,
you get the same old results!
RECALL:
ptotal initial = ptotal final
if no NET external force is acting
ex. After being struck by a bowling ball, a 1.5kg bowling
pin sliding to the right at 3.0m/s collides head-on with
another 1.5kg bowling pin initially at rest. Find the final
velocity of the second pin if the first pin moves to the
2.5m/s to the right
right after the collision at 0.5m/s.
p. 224 #22 a)
A 65.0kg ice skater moving to the right with a velocity of
2.50m/s throws a 0.150kg snowball to the right with a
velocity of 32.0m/s relative to the ground. What is the
velocity of the first ice skater after throwing the
snowball?
2.43m/s to the right
p. 224 #22 b)
A second skater initially at rest with a mass of 60.0kg
catches the snowball. What is the velocity of the second
skater after catching the snowball in a perfectly inelastic
collision?
.0797m/s to the right
NOTE: “perfectly inelastic collision” – the objects
stick together.
NOTE: We are NOT ignoring friction!
For a linear system with two objects, there are really
only three possible scenarios:
(1) the objects start apart, collide, then end apart
2) the objects start together, then split apart
3) the objects start apart, collide, and stick together
(called a ‘perfectly inelastic’ collision)
HW 29: p. 209/ 2, 3, 4; p. 214/ 2, 4