Question

A 3.10-mm-long, 430 kgkg steel beam extends horizontally from the point where it has been bolted to the framework of a new building under construction. A 69.0 kgkg construction worker stands at the far end of the beam.What is the magnitude of the gravitational torque about the point where the beam is bolted into place?

Answer 1

Step-by-step explanation:

Given that,

The length of the beam L = 3.10m

The mass of the steam beam
`m_1` = 430kg

The mass of worker
`m_2` = 69.0kg

The distance from the fixed point to centre of gravity of beam =
`(L)/(2)`

and our length of beam is 3.10m

so the distance from the fixed point to centre of gravity of beam is

`(3.10)/(2)=1.55m`

Then the net torque is

`=-W_sL'-W_wL\\\\=-(W_sL'+W_wL)`

`W_s` is the weight of steel rod

`=430*9.8=4214N`

`W_w` is the weight of the worker

`=69*9.8\\\\=676.2N`

Torque can now be calculated

`-(4214*1.55+676.2*3.9)Nm\\\\-(6531.7+2637.18)Nm\\\\-(9168.88)Nm`

≅ 9169Nm

Therefore,the magnitude of the torque is 9169Nm