A disc of mass 100 g is kept floating horizontally in air by firing bullets, each of mass 5 g with the same velocity at the same rate of 10 bullets per second. The bullets rebound with the same speed in opposite direction. Find the velocity of each bullet at the time of impact.

Explanation

To solve the problem, we will follow these steps:

### Step 1: Understand the Forces Involved
The disc is floating in air, and the weight of the disc (mg) must be balanced by the force exerted by the bullets. The weight of the disc is given by:
\[ m = 100 \text{ g} = 0.1 \text{ kg} \]
The gravitational force acting on the disc is:
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