On a dry road,a car with good tires may be able to brake wit
On a dry road,a car with good tires may be able to brake with a constant deceleration of 4.92m/s^2.
a) How long does such a car,initially traveling at 24.6m/s,take to stop?
b) How far does it travel in this time?
c) Graph x versus t and v versus t for the deceleration.
An electric vehicle starts from rest and accelerates at a rate of 2.0 m/s^2 in a straight line until it reaches a speed of 20m/s.the vehicle then slows at a constant rate of 1.0m/s^2 until it stops.
a) How much time elapses from start to stop?
b) How far does the car travel from start to stop?
a) How long does such a car,initially traveling at 24.6m/s,take to stop?
b) How far does it travel in this time?
c) Graph x versus t and v versus t for the deceleration.
An electric vehicle starts from rest and accelerates at a rate of 2.0 m/s^2 in a straight line until it reaches a speed of 20m/s.the vehicle then slows at a constant rate of 1.0m/s^2 until it stops.
a) How much time elapses from start to stop?
b) How far does the car travel from start to stop?
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Vt=Vo+at s=Vot+at^2
1.24.6-4.92t=0 t=5s s=24.6*5-1/2*4.92*5^2=61.5m
2.20=2t1 t1=10s 20-1.0*t2=0 t2=20s t=t1+t2=30s
s1=1/2*2*100=100m 20^2=2*1*s2 s2=200m s=s1+s2=300m
1.24.6-4.92t=0 t=5s s=24.6*5-1/2*4.92*5^2=61.5m
2.20=2t1 t1=10s 20-1.0*t2=0 t2=20s t=t1+t2=30s
s1=1/2*2*100=100m 20^2=2*1*s2 s2=200m s=s1+s2=300m
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