# Highschool Physics Question Homework Help

1. Oct 27, 2013

### GoonMcFly

1. The problem statement, all variables and given/known data
Hey everyone, I'm new to this forum so Let me first introduce myself to the community. I am a grade 11 High school student from Toronto, Canada. I have joined this forum in hopes of gaining access to support whenever i need help on my Physics homework. I have a question..

So there is a Cart that weights 0.521 Kg and its on a frictionless track and its attached to a string that attaches it to a weight of an UNKNOWN MASS through a frictionless pulley.
The Track is 1 Meter long, How much mass (UNKNOWN MASS) would be required to pull the cart down to the end of the track (total distance: 1 meter) in 2 seconds? The cart travels at a constant velocity so there is no acceleration.

This picture simplifies the question.
http://i.imgur.com/083cve3.jpg?1

2. Relevant equations
The Big 5 Equations.
3. The attempt at a solution

I have figured that I am solving for the Applied Force.
I'm new to Physics so I am understandably stuck.

Last edited: Oct 27, 2013
2. Oct 27, 2013

### BrettJimison

Think of it like this:
F=ma.
You have the MASS of that cart. If you can find its acceleration, then you can find the force in Newtons. You can then convert those Newtons into kilograms, thus finding the mass of the weight.

3. Oct 27, 2013

### BrettJimison

You can find acceleration by your distance formula. This problem wouldnt make sense if the cart had a constant velocity. If its velocity was constant, there would be no force acting on it.

4. Oct 28, 2013

### CWatters

The net force on the cart is not the weight when it's accelerating.

If I remember correctly when you apply F=ma to work out the tension F the mass m is the sum of the weight and cart.