Question

if a 2 g ball is tossed at 5 m/s, at an angle of 30°, what is the initial velocity (in m/s) of the ball along the Y-axis?

what is the acceleration of the 40 degree incline?

what average force is required to stop an 1100 kg car in 8.6 seconds if the car is traveling at 72 mph?

Answer 1

1) Velocity in x direction is V cos 30 degree where as in Y direction is V sin30 degree that is  

5× 1/2 = 2.5 m/s

2) acceleration along the incline comes through force of gravity .

the component in incline direction will be g × sin 40 degree . Gives us.

9.8 × sin 40 degree = 5.78 m / s ^2

3) using impulse theoram we know impulse = Force × time . = Change in momentum.

Force × 8.6 = 1100 × 72 × 0.447 ( velocity change in m/s by multiplying 0.447)

Force ( average) = 4392.83 N

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