Answer:
Explanation:
It is given that,
Distance between the spotlight and the wall, y = 24 m
Height of the woman, h = 2 m
The woman walks toward the building at the rate of 0.6 m/s,
In the attached figure, triangle ABC and MNC are similar. So,
............(1)
When she is 2 meters from the building. So x = 24-2 = 22 m
Differentiating equation (1) i.e.
So, her shadow is decreasing at the rate of 0.059 m/s. Hence, this is the required solution.
Explanation:
Given that,
The slope of the ramp,
Mass of the box, m = 60 kg
(a) Distance covered by the truck up the slope, d = 300 m
Initially the truck moves with a constant velocity. We know that the net work done on the box is equal to 0 as per work energy theorem as :
u and v are the initial and the final velocity of the truck
(b) The work done on the box by the force of gravity is given by :
Here,
W = -24550.13 J
(c) What is the work done on the box by the normal force is equal to 0 as the angle between the force and the displacement is 90 degrees.
(d) The work done by friction is given by :
Hence, this is the required solution.