Physics: work

[scan]

anyone physic experts know how to do this questions?

A force of 25 N parallel to a 35degrees inclined plane pulls a 2.5 kg block 5 m up the plane at
constant speed.
(a) How much work has been done by the 25 N force?
(b) much work has been done by friction?
(c) How much work has been done by the gravitational force?

[Parth Dave]

What have you done to try and solve the question? Where specifically are you have problems?

[WCU]

work=F(average)*(cos theta)*distance
friction=coefficient of friction * Normal force
gravity is always 9.80m/s^2 on earth

[scan]

this is what i got so far. W = F * distance

so by the diagram I got:

W = 25 N * 5m * cos 35

but i know thats wrong... i dont' know how i incorporate teh mass

[WCU]

multiply the mass by gravity, but remember that gravity will be straight down and the normal force is perpendicular to the block, so use a net force diagram to sort out the remaining forces ... hope that helps, makes more sense in my head than it does typed, lol

[scan]

multiply the mass by gravity, but remember that gravity will be straight down and the normal force is perpendicular to the block, so use a net force diagram to sort out the remaining forces ... hope that helps, makes more sense in my head than it does typed, lol


what part of the question are you refering to?

[scan]

for part a i got 102.4 J. does that look right?