Transcript Impulse

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F = Δp/t
Δp = Ft
Impulse is defined as the force times the time
over which the force acts
Impulse = Ft = Δp
In order to change the momentum of an
object, two quantities are important (Force
and time)
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Golf – to impart the greatest momentum to a
ball, its not only the force you hit the ball
with but also how long you’re in contact that
matters
Why use a seat belt?
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Area under a force vs. time curve is impulse
which is equal to the change in momentum
Assuming a 65g tennis ball started from rest
and the force of impact of the racket on the
ball is represented below, what is the impulse
acting on the ball and its final speed?
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A billiard ball of mass 200g rolls towards the
right-hand cushion of a billiard ball table at
2.0 m/s and rebounds straight back at
2.0m/s. A) What impulse acts on the ball? B)
If the time of interaction is 2.0s, what force
acts on this ball?
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A 2.0 kg skateboard is rolling across a
smooth floor when a girl kicks it causing it to
speed up to 4.5m/s in .50s. If she exerts a
force of 6.0N while kicking, what was it’s
initial velocity?
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A) Calculate the impulse experienced when a
70kg person lands on firm ground after
jumping from a height of 3.0m. B) If it takes
.003 s to stop when landing straight legged,
what is the force of impact? C) If it takes
.13s to land when your knees are bent, what
is the force of impact?