Answer:
The increase in the gravitational potential energy is 29.93 joules.
Explanation:
Given that,
Mass of the box, m = 2.35 kg
It is lifted from the floor to a tabletop 1.30 m above the floor, h = 1.3 m
We need to find the increase the gravitational potential energy. Initial it will placed at ground i.e. its initial gravitational potential is equal to 0. The increase in the gravitational potential energy is given by :


U = 29.93 Joules
So, the increase in the gravitational potential energy is 29.93 joules. Hence, this is the required solution.
Answer:
It would change the amount of heat produced in the transmission line to four times the previous value.
Explanation:
Given;
initial voltage in the transmission line, V₁ = 500 kV = 500,000 V
Final voltage in the transmission line, V₂ = 1 MV = 1,000,000
The power lost in the transmission line due to heat is given by;

Power lost in the first wire;


Power lost in the second wire

Keeping the resistance constant, we will have the following equation;


Therefore, it would change the amount of heat produced in the transmission line to four times the previous value.