Much of the energy of falling water in a waterfall is converted into heat. If all the mechanical energy is converted into heat that stays in the water, how much of a rise in temperature occurs in a 111 m waterfall?

Explanation:

potential energy of water is converted into heat energy

P E = mgh = m x 9.8 x 111

= 1087.8 m .

Let rise in temperature θ

m x s x θ = heat absorbed

m x s x θ =  1087.8 m

m x 4182 x θ =  1087.8 m

θ = 0.26 degree celsius .

weight of the box is given as

here this is placed on the inclined of angle 42 degree

now this weight will have two components one is along the incline other is perpendicular to it

so here we need to apply a force parallel to incline opposite to its component of weight

so here the component of weight is given as

here we have

so it requires 75 n force to move it upwards