Complete Question
The complete question is shown on the first uploaded image
Answer:
1 The time it would take for the bob to return back is

2 small angle approximation mean that the sin of that angle which in radians is equal to the angle i.e

This approximation do reach an error of 1% at about 10° hence the small approximation is for angle less than 10°
Step-by-step explanation:
From the question we are told that
The mass of the pendulum is

The length of the cable is

The length of the hook from the floor is

Generally the Time period of a pendulum is not dependent on mass
And this time period is mathematically represented as

Substituting values
