Question

Your friends car is parked on a cliff overlooking the ocean on an incline that makes an angle of 17.0° below the horizontal. The brakes fail, and the car rolls from rest down the incline for a distance of 29.0m to the edge of the cliff, which is 55.0m above the ocean, and, unfortunately, continues over the edge and lands in the ocean.

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

h = 29*sin17 = 8.48 m. = ht. of the incline.

V1^2 = Vo + 2g*h = 0 + 19.6*8.48 = 166.2, V1 = 12.9 m/s[17o] = Velocity at bottom of the incline.
X1 = 12.9*Cos17 = 12.3 m/s.
Y1 = 12.9*sin17 = 3.77 m/s.

Y2^2 = Y1^2 + 2g*h = 3.77^2 + 19.6*55 = 1092.2, Y2 = 33 m/s. = Final velocity.

Y2 = Y1 + g*t = 33, 3.77 + 9.8t = 33, 9.8t = 29.23, t = 2.98 s.

a. Dx = X1*t = 12.3 * 2.98 = 36.7 m.

b. T = 2.98 s (Calculated above).

Answer 2

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