Question

8.
Two boys are holding a horizontal rod of
length L and weight W through its two ends.
If now one of the boys suddenly leaves the
rod, what is the instantaneous reaction force
experienced by the other boy?
1) w/4
2)w/2
3)3w/4
4)w​

Answer 1

Answer:

The instantaneous reaction force at one end experienced by the boy is w/4

Explanation:

As we know that two boys are holding the rod at two ends

Now when one boy suddenly leaves the one end of the rod then by torque equation about one end of the rod

$\tau = I \alpha$

$mg(\frac{L}{2}) = \frac{mL^2}{3} \alpha$

$\frac{3g}{2L} = \alpha$

now acceleration of center of mass of the rod is given as

$a_{cm} = \frac{L}{2}\alpha$

$a_{cm} = \frac{3g}{4}$

now by force equation of rod

$mg - F_n = ma$

$mg - F_n = m(\frac{3g}{4})$

$F_n = \frac{mg}{4}$

$F_n = \frac{w}{4}$

here we know that

$w = mg$

#Learn

Topic = Torque on rod

https://brainly.in/question/14162167

Answer 2

Explanation:

Hope this helps you !!!!