seat belt physics

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seat belt physics
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Physics Zone Forces, accelerations, and car
accidents

• car crashes

3
What does bungee jumping, trampoline jumping and
falling into trapeze nets all have in common?
?KE F d
4
Why have the number of injuries sustained by
football players increases since the advent of
artificial turf?
5
How much work is done on the satellite by Earth
while orbiting?
6
Total work done on a ball

• Lifting the ball 1 m at constant velocity.
• Holding the ball stationary
• Walking 1 m with the ball at constant velocity
• Lowering the ball 1 m at constant velocity

7
A 15.0-kg block starts from rest and slides 5.0
m on a frictionless 30.o incline. How much
work is done by gravity? What is the total work
done on the block? What is the speed of the
block at the bottom?
8
A rock is dropped from rest and travels 10.0 m
before hitting the ground. What is the speed of
the rock just before it hits the ground?Solve
this problem using both the work-energy theorem
and kinematics
9
A catcher stops a 90 mph pitch. Has the catcher
done positive work, negative work or zero work on
the ball?Justify your answer using the
definition of work as well as the work-energy
theorem.
10
Two 1.0-kg blocks starts from rest and slide on
frictionless 30.o and 60.o inclines from a height
of 1.0 m. What is the distance traveled by each
block? What is the gravitational force exerted
on each block? Which block has more work done
on it by gravity? What is the total work done
on each block? Which block is moving faster at
the bottom?