A uniform metre rule of weight 10gf is pivoted at its 0 mark.(i) What

1.	A uniform metre rule of weight 10gf is pivoted at its 0 mark.(i) What moment of force depresses the rule?(ii) How can it be made horizontal by applying a least force?
Answer» (i) Anticlockwise moment= 10gf × 50 cm = 500gf cm (ii) From the principle of moments, Anticlockwise moment = Clockwise moment 10gf × 50 cm = W × 100cm So, W = 10gf x 50cm/100cm = 5gf By applying a force 5 gf upwards at the 100 cm mark, rule can be made horizontal

A uniform metre rule of weight 10gf is pivoted at its 0 mark.(i) What moment of force depresses the rule?(ii) How can it be made horizontal by applying a least force?

Answer»

(i) Anticlockwise moment= 10gf × 50 cm = 500gf cm

(ii) From the principle of moments,

Anticlockwise moment = Clockwise moment

10gf × 50 cm = W × 100cm

So, W = 10gf x 50cm/100cm = 5gf

By applying a force 5 gf upwards at the 100 cm mark, rule can be made horizontal