Question

please tell the answer

question number 5​

Answer 1

Answer:

Given:

A body is dropped from the edge of a roof .

To find:

• Time taken to travel 4.9 metres
• Speed at that position
• How the body moves at 7.9 metres
• What is the acceleration after 1 second and 2second.

Calculation:

Since ball is dropped from edge, we get initial Velocity to be zero.

1. s = ut + ½gt²

=> 4.9 = 0 + ½ × (9.8) × t²

=> t = 1 second.

2. Speed at that position :

∴ v = u + gt

=> v = 0 + (9.8) × 1

=> v = 9.8 m/s

3. Speed at 7.9 metres:

∴ v² = u² + 2gh

=> v² = 0 + 2(9.8)(7.9)

=> v² = 148.96

=> v = 12.20 m/s

4. Acceleration at the end of 1 sec and 2 second will be equal to Acceleration due to gravity (i.e 9.8 m/s²)