# physics

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A 14.5 kg ring has 3 ropes attached to it. One rope is being pulled due North with a force of 340 N. Another rope is being pulled 68 degrees South of West with a force of 450 N. How hard and in what direction must the third rope be pulled in order to cause the ring to move 15 degrees North of East? How far will the ring have moved after 28 s?

• physics - ,

This is fairly easy on a polar graph. Draw vectors1 and 2, and a line representing the direction of movement.

graphically add 1 and 2, getting a resultant r.

Now r added to some third vector must equal someting along the line for the movement at 15N of E. You will need a polar graph, straight edge, probably a compass. A parallel motion protractor would make it easy, but they are not so available today.
Have fun.

• physics - ,

I don't have a polar graph, never even heard of it. Is there any way to do this with equations?

• physics - ,

Polar graph is pretty common.

http://mason.gmu.edu/~mmankus/Handson/polar.htm

The equations are messy.

• physics - ,

k I'll try it, thanks.