3. SPIDEY IN ACTION
STOP
DIFFICULTY
MOTION
What is Spider-Man doing in
the video?
Did he find it easy to stop
the train?
What do you think are the
reasons why he suffered
difficulty in stopping the
train?
13. A 360,000 kg passenger plane
lands on the runway with a
velocity of 1.5 m/s. Determine its
momentum.
Sample Problem
14. The parking brake of a 1200kg
automobile has been broken, and
the vehicle has reached a
momentum of 7800kg*m/s.
What is the velocity of the
vehicle?
Sample Problem
15. Sample Problem
A 325 kg motorcycle is moving at 38.89 m/s, east.
a. Find its momentum
b. At what velocity is the momentum of a 1754 kg car to
that of the motorcycle.
16. Why does knowing the momentum and the stopping distance
of vehicles important in driving safely?
17. In a baseball game, why
does the batter need to
swing back the bat
before hitting the ball?
18. IMPULSE
-change in momentum
- is the change of momentum of an
object when the object is acted upon
by a force for an interval of time
19. For us to change the momentum of an object (impulse), we
need to apply an amount of force (impact force) within a
specific amount of time (impact time).
FORCE TIME IMPULSE
F t I
N s N•s
In symbols
In SI units
21. A hockey player applies an average force of 80.0 N
to a 0.25 kg hockey puck for a time of 0.10 seconds.
Determine the impulse experienced by the hockey
puck.
Sample Problem
22. Jennifer, who has a mass of 50.0 kg, is riding at 35.0 m/s in her red sports
car when she must suddenly slam on the brakes to avoid hitting a deer crossing
the road. She strikes the air bag that brings her body to a stop in 0.500 s.
What average force does the seat belt exert on her?
Sample Problem