A car is parked on a cliff overlooking the ocean on an incline that makes an angle of 21.0° below the horizontal. The negligent driver leaves the car in neutral, and the emergency brakes are defective. The car rolls from rest down the incline with a constant acceleration of 3.37 m/s2 for a distance of 60.0 m to the edge of the cliff, which is 30.0 m above the ocean.

Question

(a) Find the car's position relative to the base of the cliff when the car lands in the ocean.

(b) Find the length of time the car is in the air.

Answer 1

60 = (1/2)(3.37) t^2
solve fot t, the rolling time
v = a t = 3.37 t
that v is the speed at the cliff edge

u = v cos 21 = horizontal speed until bottom

Vi = -v sin 21 = initial speed up (negative of course)

h = Hi + Vi t + (1/2) a t^2
now t is the time airborne
0 = 30 - v (sin 21) t - 4.9 t^2
solve for time in the air

d = u t = v ( cos 21) t

Answer 2

What would be the answers to A and B?