Answer:
There are 45 turns in the secondary coil.
Explanation:
Given that,
Input potential of the lamp, 
The output potential of the lamp, 
Number of turns in primary coil, 
We need to find the number of turns needed on the secondary coil. We know that the ratio for a transformer is as follows :

So, there are 45 turns in the secondary coil.
<u>Answer:</u> The velocity of released alpha particle is 
<u>Explanation:</u>
According to law of conservation of momentum, momentum can neither be created nor be destroyed until and unless, an external force is applied.
For a system:

where,
= Initial mass and velocity
= Final mass and velocity
We are given:

Putting values in above equation, we get:

Hence, the velocity of released alpha particle is 
Zeroth Law of Thermodynamics, which in turn will mean the heat will transfer between both of them up to the point where they are in thermodynamic equilibrium. So the answer is C.