Answer:
66.6 kg
Explanation:
The weight of a person at Earth's surface is given by

where
m is the mass of the person
is the acceleration of gravity
The person in the problem has a weight of
W = 653 N
Therefore, we can rearrange the equation to find his mass:

You got it right on the top 3
Answer:
Length of the pendulum will be 3.987 m
Explanation:
We have given time period of the pendulum T = 8 sec
Acceleration due to gravity 
We have to find the length of the simple pendulum
We know that time period of the simple pendulum is given by



So length of the pendulum will be 3.987 m
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