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hello, i have some questions to do but am unsure where to start on some of them, the first one is

[assume the earths gravitational pull is 10n]

1)"A motor vessel tows a small dinghy by a rope which makes an angle of 20 degrees to the horizontal. The Tension in the rope is 150n"

a)what is the value of the force that pulls the dingy in the forwards direction?

b)what is the value of the vertical force lifting the bows out of the water? [i don't know what bows is maybe the sheet hasa typo and it means boats?

2)a garden roller has a mass of 70kg. A man exerts a force of 200n on it at an angle of 45 degrees to the ground.

Find the verticle force of the roller on the ground:

a)if he pulls the roller

b)if he pushes the roller

4)a river is 50m wide. A rowing boat sets off across the river aiming for a point on the opposite bank perpendicularly opposite the starting point. However, as a result of the the current in the river, the boat actually ends up 30m downstream of the intended landing point. It takes 75s for the boat to cross the river.

a)What distance does the boat actually travel

b)what is the resultant velocity of the boat

c)what is the velocity of the current in the river? [assume the current is the same at all points in the river

d)with what speed would the boat move in still water?

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for question 1a, i didn't understand what it meant by "to the horizonal", but anyway i drew a little diagram and used Sin=O/H , rearranged to Sin*H=O to get Sin20*150=136.84n [tp 2 dp]

for question b i had no idea what it means

for question 2 i tried drawing a sketch but am not sure what to do. the garden roller must exert a 700n force to the ground, and the man a 200n at a 45 degree again, but then the question just confuses me by asking what direction he is pushing or pulling, as if he pulls the roller isn't he no longer exerting the 200n force upon the mower, ahh i'm confused

for question 4a i used pythagoras to get 50^2+30^2= sqrt:3400which is 58.30m two dp

for b i used just speed=distance/time but i don't think that is the correct choice of equation [bit too basic, i'm not sure?] but anyway i got 0.77m/s for that one

for c) and d) i have no idea where yo start?

can anyone offer any points to get me started on thw questions i'm stuck on [as well as seeing if my existing aswers are correct?]

thanks if you can help :D

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# Homework Help: Resolving vectors problems [whoops sorry didn't see there was a Hw section move]

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