Answer:

Explanation:
We need to find the energy for an electron to jump from n = 1 to n = 4.
The energy in transition from 1 state to another is given by :

The difference in energy for n = 1 to n = 4 is:

So, the required energy is equal to
.
Torque [Nm] = Force [N] x Force arm [m]
C=F*b=20*0.20=4 Nm
The correct answer is C
Political power is utilized in a roundabout way by chose authorities, not straightforwardly by the natives themselves. Oftentimes, legislators and numerous standard Americans allude to the United States as a majority rules system. Others locate this disturbing in light of the fact that, not at all like in a vote based system where nationals vote specifically on laws, in the United States, chose agents do – and, thusly, the U.S. is a republic.
In empty space probably means, there is no force on the ball.
(This assumption is not quite correct since there is still the force of gravity between the ball and the astronaut, but this force is very very small and can be neglected.)
Assuming there is no force on the ball, Newtown's 1st law says: When viewed in an internal frame of reference, an object either remains at rest or continues to move at a constant velocity, unless acted upon by a force.
This means:
If there is no force on the ball, there will be no acceleration on the ball either.
If the acceleration is zero, the velocity of the ball never changes.