Answer:
(a) Velocity of target is 2.7 m/s.
(b) Mass of target is 0.807 kg.
Explanation:
Mass of ball 
initial speed of the ball 
Final speed of the ball 
Part (a) The second ball is initially at rest. So, by the conservation of momentum,

Now, the velocity of approach is equal to the velocity of separation,

Part (b): From equation (1),

Answer:

Explanation:
From the question we are told that:
Distance of wall from CD 
Second bright fringe 
Let
Strontium vapor laser has a wavelength \lambda= 431 nm=>431 *10^{-9}m
Generally the equation for Interference is mathematically given by

Where



Explanation:
In the given situation two forces are working. These are:
1) Electric force (acting in the downward direction) = qE
2) weight (acting in the downward direction) = mg
Therefore, work done by all the forces = change in kinetic energy
Hence,
It is known that the weight of electron is far less compared to electric force. Therefore, we can neglect the weight and the above equation will be as follows.

v = 
= 592999 m/s
Since, the electron is travelling downwards it means that it looses the potential energy.
Answer:
Alpha radiation is the name for the emission of an alpha particle in fact an helium nuclei, beta radiation is the emission of electrons or positrons , and gamma radiation is the term used for the emission of energetic photons.
Explanation: