Question

A question involving a pulley and a boat

Answer 1

The rope and the height, h, and the distance, d, form a right triangle, with the angle @ between the rope and the horizontal. The projection of a unit of rope length on the horizontal is cos@, so the projection of 0.4m/s is (0.4 m/s) cos @. Get @ from @=arc tan(10/30.

Answer 2

wait sorry, is it arc tan(10/3) or arc tan (10/30)? and where does the 30 come from?

Answer 3

arc tan (10/3)
I hit 0 instead of ) sorry.

Answer 4

explain to me Callisto :(

Answer 5

You want to know how much horizontal distance changes per unit change in rope length and that factor is cos@, but @ keeps changing. They tell you the boat is 3 feet from dock and the pulling is from 10 feet above the water level.

Answer 6

ok I understand it now, thanks. I also saw similar questions online and supposedly you can use related rates to solve it as well?

Answer 7

You didn't try it yourself at all? You'll have to do better than that on your exams.

Answer 8

I did try to do it myself but I was stuck and I know that.

Answer 9

Fair enough. Just checking.