Question

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

Answer 1

This one's probably about moments. If would be helpful to draw a diagram to visualize the respective forces acting on the rod. (so you would have balances C and D at each end of the rod, exerting an upward force on the rod. The weight of the rod exerts a downward force on the middle of the rod)
To examine the reading on each balance, take the other balance as a pivot.
Moment = Force x Distance from pivot
For example, if we want to find the reading on Balance D, Balance C is the pivot. 2 forces are acting on the rod - it's weight, and the upward countering force exerted by Balance D. Since the rod is assumed to be in equilibrium,
the moments exerted by both forces are the same:
Weight x Distance from pivot = Balance D x Distance from pivot
The distances from the pivot of the respective forces should be easy to calculate with a diagram.
Then repeat the same with balance D

Answer 2

Physics

Answer 3

So the u will take 3.2kg ad use it in c and d

Answer 4

So u will take3.2kg and use to c and d

Answer 5

Reading on spring C is 106N
Reading on spring D is 213.3N

Answer 6

Calculations