n small droplets of water, each of radius r, coalesce ot form a single drop of radius R. Find
(i) Velocity acquired by bigger drop if all the energy released is converted into kinetic energy.
(ii) Rise in temperature.
Take, surface tension of water `=sigma`
Mechanical equivalent of heat =Q

Explanation

To solve the problem, we will break it down into two parts as requested.

### Part (i): Velocity Acquired by the Bigger Drop

1. **Understanding the Problem**: We have `n` small droplets of water, each with a radius `r`, that coalesce to form a single larger droplet with radius `R`. We need to find the velocity `v` of the larger droplet if all the energy released during this process is converted into kinetic energy.

2. **Volume Conservation**: The volume of the small droplets must equal the volume of the larger droplet:
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