problem involving vectors?

Question

plz. explain how to do it.


A ramp could be used to raise the concrete 20 m.
a) How much work would be required if the ramp formed at an angle 30 degrees with the horizontal?
b) How long would the ramp be?
c) How much force would be required?
(The component of the force // to the ramp.)
(Neglect friction)

Answer 1

a) W= m*9.8*20 Joule where m is the mass of concrete in kg
b)cos 30 = 20/L so L = 40/3* sqrt 3
F*L = m*g * 20
so F = m*9.8 *20 *3/(40*sqrt 3) =1/2* m *9.8*sqrt(3) Newton