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Homework Statement
For my physics practical I have to conduct an experiment where I have to investigate the acceleration of a small cart, its a block of wood with wheels on it.
The set up is I have a one metre distance marked on a desk from the edge of the desk. at the edge of the desk is a pulley wheel. The cart is placed at the start of the metre distance and then tied to a piece of string which goes over the pulley and then connects to weights which pull the cart towards the pulley.
The problem is we have to basically at the end of the experiment show how this is relevant to the formula, f=ma, and therefore Newtons second law, without stating it.
However we have to predict whether that acceleration of the cart will be proportional to the force of the weights or whether it will be directly proportional to the force. I can obviously tell it shall be directly proportional from my knowledge of Newtons second law. However I can't figure out how to explain my prediction without using this law?
He told us that we could and had to use Newtons first law to back this up and also some other general physics as well.
Homework Equations
F=ma, but I can't use it.
The Attempt at a Solution
The closest I have came to explaining is that if Newtons first law states that an object will remain at rest or constant speed as long as no resultant force acts upon it, then the weights are a resultant force which will cause the cart to change from being at rest to a state of motion and that this motion shall be accelerating as the resultant force will still be acting upon the cart.
However that doesn't explain how the acceleration will be directly proportional to the force