Advertisements
Advertisements
Question
A boy of mass 30 kg is fitting at a distance of 2 m from the middle of a see-saw. Where should a boy of mass 40 kg sit so as to balance the see-saw?
Advertisements
Solution
By the principle of moments 30 × 2 = x × 40
∴ Other boys should sit at a distance
x =`(30xx2)/40`
= 1.5 m
APPEARS IN
RELATED QUESTIONS
State two condition for a body acted upon by several forces to be in equilibrium.
A uniform meter scale is in equilibrium as shown in the diagram :
(i) Calculate the weight of the meter scale.
(ii) Which of the following options is correct to keep the ruler in equilibrium when 40 gf wt is shifted to 0 cm mark ?
F is shifted towards 0 cm
or
F is shifted towards 100 cm
The arms of a beam balance are 20 cm and 21 cm, but the pans are of equal weight. By the method of double weighing the weights are found to be 1000 g and 20 g. Find the actual weight of the body
The moon revolving around the earth is in ______ equilibrium.
In figure, a uniform bar of length l m is supported at its ends and loaded by a weight W kgf at its middle. In equilibrium, find the reactions R1 and R2 at the ends.
`["Hint:" "In equilibrium" "R"_1 + "R"_2 = "W" "and" "R"_1 xx l/2 = "R"_2 xx l/2]`
What is the weight of a body placed at the centre of the earth?
What is a couple?
One end of a spring is kept fixed while the other end is stretched by a force as shown in the diagram.
(i) Copy the diagram and mark on it the direction of the restoring force.
(ii) Name one instrument which works on the above principle.
A ball is placed on a compressed spring. When the spring is released, the ball is observed to fly away.
(i) What form of energy does the compressed spring possess?
(ii) Why does the ball fly away?
How can we increase the stability of an object?
