1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

# A triangular set square of angle 30∘,60∘ and 90∘ and of negligible mass is suspended freely from the right-angle corner and weights are hung at the two corners. If the hypotenuse of the set square adjust horizontally, then the ratio of the weights W1W2 is 1:n. The value of n is (integer only)

Open in App
Solution

## The hypotenuse will be oriented horizontally only when torque on the hypotenuse becomes zero. Using, principle of moments, Clockwise torque about point D = Anticlockwise torque about point D W2(BD)=W1(AD) ⇒W1W2=BDAD .......(1) Now, From the diagram, Let AB=l AC=lcos30∘ ; BC=lcos60∘ ⇒AD=ACcos30∘=lcos230∘ ⇒BD=BCcos30∘=lcos260∘ Putting this values in (1) we get, ∴W1W2=BDAD=cos260∘cos230∘=1434=13 Hence, n=3 Why this question ? This question involves idea of rotational equilibrium, when object is in rotational equilibrium, net clockwise torque and net anticlockwise torque about axis of rotation will be equal.

Suggest Corrections
0
Join BYJU'S Learning Program
Related Videos
Angular SHM
PHYSICS
Watch in App
Explore more
Join BYJU'S Learning Program