- #1

- 15

- 0

## Homework Statement

A stunt car is driven off a cliff with a speed of 110 ft/s. What is the gravitational acceleration of the car normal to its path after falling for 3 seconds?

## Homework Equations

The kinematic equations...?

I'm pretty sure that this should be done in Normal and tangential components, so with that said:

[itex] s = \theta r [/itex]

[itex] a_t = \dot{v} = v \frac{dv}{ds} = \alpha r [/itex]

[itex] v = \dot{s} = \omega r [/itex]

[itex] a_n = \frac{v^2}{\rho} = \omega^2 r [/itex] Where [itex] \rho [/itex] is the radius of curvature.

## The Attempt at a Solution

For the x-direction:

[itex] (v_0)_x = 110 [/itex]

[itex] t = 3 [/itex]

[itex] \Delta x = (v_0)_x t = (110)(3) = 330 [/itex]

For the y-direction:

[itex] y = y_0 + (v_0)_y t + \frac{1}{2} a t^2 [/itex]

Solving for distance in the y-direction:

[itex] y = \frac{1}{2}(-g)t^2 \quad (t = 3) [/itex]

[itex] y = -144.9 ft [/itex]

But I really have no idea if any of that is necessary, or if it is where do I go from there?