## Tuesday, October 25, 2011

### How do I determine the mass of a car without turning the car on?

My physics lab requires me to find the mass of a van without turning it on. My group can move the car, but we cannot turn it on. We can use the following items:

-3 Bathroom scales

-1 Stopwatch

-1 Measuring tape

I have to incorporate friction. To find the friction coefficient, we will push the car at a constant velocity with the bathroom scales between us and the car. The total force shown on the scales will be the amount of force needed to overcome friction resistance. I do not know what to do after that.
How do I determine the mass of a car without turning the car on?
You have to use the stop watch to find the amount of time it takes to accelerate the van a measured distance (using the measuring tape). If you know the starting velocity (0m/s), the distance traveled (measured), and the time it takes to travel the measured distance, you can calculate the acceleration of the van.

x(t) = 1/2 a t^2

Using the scales you can measure the average force applied to accelerate the van.

Using F=ma , you can solve for the mass.
How do I determine the mass of a car without turning the car on?
Put two scales under the front wheels and record the weigh. Repeat for the rear wheels. Add them up. Use acceleration of gravity constant to convert to mass. Scales must work for 1/4 of the weight.

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