Question

A uniform metal rod of length 80cm and mass 3.2 kg is supportedhorizontally by the two verticalsprings balances C and D. Balance C is 20 cm from one end while balance D is 30 cm from the other end. Find the reading on each balance.​

Answer 1

To find the reading on each balance, we can use the principle of moments and equate the total anticlockwise moment to the total clockwise moment. The readings on Balance C and Balance D will be equal to 64 kg cm.

Step-by-step explanation:

To find the reading on each balance, we can use the principle of moments. The total anticlockwise moment about one end of the rod must be equal to the total clockwise moment about the same point. Balance C is 20 cm from one end, so its moment is given by (mass of rod) x (distance from end) = 3.2 kg x 20 cm.

Balance D is 30 cm from the other end, so its moment is given by (mass of rod) x (distance from end) = 3.2 kg x 30 cm.

Equating these two moments will allow us to solve for the readings on each balance.

Let's calculate the moments:

1. Moment from Balance C = (3.2 kg)(20 cm) = 64 kg cm
2. Moment from Balance D = (3.2 kg)(30 cm) = 96 kg cm

Since the total anticlockwise moment must be equal to the total clockwise moment, we have:

64 kg cm = 96 kg cm

Therefore, the readings on each balance will be equal to 64 kg cm.

Learn more about principle of moments