Answer: 
Explanation:
This problem can be solved by the following equation:

Where:
is the change in kinetic energy
is the electric potential difference
is the electric charge
Finding
:


Finally:

Answer:
Newton
Explanation:
The earth attracts every body towards its centre. The force with which the earth attracts any body towards its centre, is called its weight.
It is a vector quantity.
It always acts towards the centre of earth.
The SI unit of Newton.
The first step would be to create an electromagnet. You can create an electromagnet by winding a copper wire around the nail, the connect both ends to the battery. A current would start flowing around the nail through the wire, creating an electromagnet with its own magnetic field. Next, bringing the electromagnet to the mixture of copper and iron would slowly attract the pieces of iron (as copper is weakly magnetic). Do this slowly and the iron pieces would all slowly be separated from the copper pieces.
Answer:
m2 = 83.3 g
Explanation:
by conservation of momentum principle we have

as both sphere has same speed so 

from conservation of kinetic energy principle we have




substituting this value in above equation to get m2 value

solving for m2 we get

m_1 = 250 g

m2 = 83.3 g