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F= ___ N
1) Copy this diagram into your book, under the above title.
2) Hang the mass from the newtonmeter, lift it from the floor.
Hold it still.
Write down the size of the force which you measure.
3) Look at the scale on the newtonmeter, how accurate is it? How many decimal places should you use to write down your measurement?
Forces always come in equal and opposite pairs. Gravity pulls down, creating weight, and tension in the string pulls up.
3) The dotted arrows represent forces. Label these arrows in your book as "weight" and "tension".
4) Raise the mass from the floor to your knee. Measure the height to your knee. How much work did you do?
First write down all the variables in the formula, then write down your calculation. It might look like this:
Force = 123.4 N
Distance = 23 cm = 0.23 m
Work = Force x Distance = 123.4 N x 0.23 m = 28.4 J
5) Copy this diagram into your book.
6) Pull the string across the pulley to lift the weight.
Hold it still.
Write down whether the force is the same as before or not.
7) The arrow for tension is missing. Add an arrow to your diagram (at the dot) to show which direction tension is pulling.
8) Pull the string across the pulley to lift the weight again.
Look at the newtonmeter while it is moving.
Is the force greater, less, or the same compared to when the weight is being held still?
9) Lower the weight to the floor.
Look at the newtonmeter while it is moving.
Is the force greater, less, or the same compared to when the weight is being held still?
Pulleys