Answer:
<h2>Force due to biceps is given as</h2><h2>

</h2>
Explanation:
For balancing the force we know that
Torque due to weight hold on his hand = torque due to force applied by biceps
So here we will have

so we have


Answer:
2.When they reach the bottom of the fall
Explanation:
The potential energy of the waterfall is maximum at the maximum height and decreases with decrease in height. Based on the law of conservation of mechanical energy, as the potential energy of the water fall is decreasing with decrease in height of the fall, its kinetic energy will be increasing and the kinetic energy will be maximum at zero height (bottom of the fall).
Thus, the correct option is "2" When they reach the bottom of the fall
Temperature is the measurement system we use to measure the heat