please answer 3 questions

Question

1. (a) Using a small pendulum of length .234m, a student on top of a tree counts 80 oscillations in 70 seconds. What is the value of ‘g’ in this location?  

(b) What is the length of the pendulum.

(c) What is the frequency and angular frequency?

Answer 1

T = 2pisqrt( length/ Acceleration due to gravity)

T ² = 4 pi² ( Length/ Acceleration due to gravity)

Acceleration due to gravity = 4pi² ( Length/T² )

T = 70/80 = 7/8 Sec

Acceleration = 4* 22*22*0.234*8*8/ ( 7*7*7*7) = 12.076 m/s2

Use angular frequency = 2pi/T

and

frequency = 1/T