(Solved): please help with all 3! A helicopter. starting from rest, accelerates straight up from the roof of a ...

A helicopter. starting from rest, accelerates straight up from the roof of a hospital. The lifting force does work in raising the helicopter. An $$860-\mathrm{kg}$$ helicopter rises from rest to a speed of $$8.5 \mathrm{~m} / \mathrm{s}$$ in a time of $$3.0 \mathrm{~s}$$. During this time it climbs to a height of $$9.6 \mathrm{~m}$$. What is the average power generated by the lifting force? The graph shows how the force component $$F \cos \theta$$ along the displacement varies with the magnitude s of the displacement. Find the work done by the force. (Hint: Recall how the area of a triangle is related to the triangle's base and height.) A net external force is applied to a $$6.49-\mathrm{kg}$$ object that is initially at rest. The net force component along the displacement of the object varies with the magnitude of the displacement as shown in the drawing. What is the speed of the object at $$s=20.0 \mathrm{~m}$$ ?