Answer:
Magnetic force, attraction or repulsion that arises between electrically charged particles because of their motion. It is the basic force responsible for such effects as the action of electric motors and the attraction of magnets for iron. Electric forces exist among stationary electric charges; both electric and magnetic forces exist among moving electric charges. The magnetic force between two moving charges may be described as the effect exerted upon either charge by a magnetic field created by the other.
As we know that :

Power, is in Meter. So divide focal length by 100

Answer:
wavelength = v/f or wavelength equals to velocity over frequency
frequency= v/w or velocity over wavelength
frequency= 1/p or one over period or time
Answer:
5 m/s
Explanation:
Here we can see there is no external force acted on a two masses when we consider the motion. If there is no external forces then momentum is conserved.
Initial momentum = Final momentum
0.5 × 10 = 1 × V
V = 5 m/s