Answer:
False
Explanation:
There is less pressure higher in the atmosphere, which means that air will expand, and thus cool
U is correct on the first one
Answer:

Explanation:
The potential produces by a point charge is given by:

Here, k is the Coulomb constant, q is the signed magnitude of the point charge and r is the distance between the charge and the point at which the electric potential is measured. Solving for q:

Answer:
D
Explanation:
D) The overall work done by gravity is zero
This statement is correct .
If m be the mass of each of the children and h be the height of tower
work done by gravity on the boys in going up = - mgh
it is so because force applied by gravity = mg downwards and displacement
is upwards
work done will be negative = - mgh
Work done by gravity on boys when they come down = + mgh because both force and displacement are downwards .
Hence total work done = - mgh + mgh = 0.
The children will have same kinetic energy as the inclined surface is friction-less so no energy will be dissipated hence addition of energy to boys in both the cases will be same.
The current in the circuit =5 A
Explanation:
Voltage = 60 V
resistance= 12 ohm
using ohm's law V=i R
60= i (12)
i=60/12
i=5 A
Thus the current flowing in the circuit = 5 A