# Help with lab - final velocity of total distance

1. Sep 17, 2009

### texan717

1. The problem statement, all variables and given/known data
All right so this will probably sound a little muddled but I'll try anyway. We conducted a lab today in class. We were given a hot wheels car, a meter stick, a ramp, and a stopwatch. We were told to find final velocity of total distance. We were not told how to actually perform this lab. Our teacher is really into making us think about how to find your answer. Anyway we decided to time how long it took the car to go down the ramp from the top to the bottom. So my first question is that right?

Assuming yes,
ramp = 51 cm in length
height = 10 cm
average time was .86 s

2. Relevant equations
y = 1/2 + at^2
vf^2 = vi^2 + 2ax

3. The attempt at a solution

All right so I can form a triangle. The vertical component is 10 cm, the hypotenuse is 51 cm.
Using the pythagorean theorem I get 50.01 cm for the horizontal. That doesn't seem to help me much. I tried using vf^2 = vi^2 + 2ax.
Initial velocity is zero. 2 * gravity * .51 m = 10.0062
The squr root of 10.0062 is 3.16 m /s. Is this the amount of vertical velocity ?

I really could use some help to know if I'm anywhere near the correct way to solve this.

2. Sep 17, 2009

### rl.bhat

Along the ramp the acceleration is less than g. Find the angle of inclination of the ramp. Then find the component of g along the ramp. Use this value in the equation you have written to find the final velocity.