**Q:** A car is parked on a cliff overlooking the ocean on an incline that makes an angle of 24.0Â° 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 4.00 m/s2 for a distance of 50.0 m to the edge of the cliff. The cliff is 30.0 m above the ocean. Find (a) the carâ€™s position relative to the base of the cliff when the car lands in the ocean, and (b) the length of time the car is in the air.

**A:** You can use this equation to find Vf as the car leaves the cliff and begins to fall:

Now you can split this velocity up into its components. As the car leaves the cliff, it forms a triangle of velocities with 20 on the hypotenuse, and Vx = 20*cos(24), Vy = 20*sin(24)

These are the initial velocities in the horizontal and vertical directions, respectively.

Use in the Vertical to solve for time.

Rearrange and use the quadratic formula, with a = -4/9, b = -20*sin(24) and c = 30

You should find that **t = 1.78 seconds**.

You can then use this time in D=VT in the horizontal, to solve for D.

D=VT

D = 20*cos(24) * 1.78

**D = 32.5 m**

Hope that makes sense!

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