A person weighing 45 kg sits in one end of a see saw while a boy of 15 kg sits on the other end. If they are separated by 4 m , how far from the boy the centre of mass situated. Neglect the weight of the see saw.

Open in App

Solution

Let the equilibrium is at a distance a meter from boy
=>it is (4 - a) meter from the 45 kg person
So m1r1=m2r2
=>a x 15 = (4 - a) x 45
=>15a = 180 - 45a
=>60a = 180
=>a = 180/60 = 3 meter
Therefore the centre of mass of body will be situated 3m away from the boy

Suggest Corrections

Similar questions

Q. A boy weighing

20 k g

is sitting at one end of a see-saw at a distance of

1.2 m

from the centre. Where should a man weighing

60 k g

sit on the see-saw, so that it stands balanced?

Q. When a boy weighing

20 k g f

sits at one end of a

4 m

long see-saw, it gets depressed at this end. How can it be brought to the horizontal position by a man weighing

40 k g f

Q. When a boy weighing

20 k g f

sits at end of a

4 m

long see-saw, it gets depressed at this end. How can it be brought to the horizontal position by a man weighing

40 k g f

When a boy weighing 20 kg sits at one end of a 4 m long see-saw, it gets depressed at this end. How can it be brought to the horizontal position by an another boy weighing 40 kg?

When a boy weighing $20 k g$ sits at one end of a $4 m$ long see-saw, it gets depressed at this end. How can it be brought to the horizontal position by another boy weighing $40 k g$ ?

Join BYJU'S Learning Program

A person weighing 45 kg sits in one end of a see saw while a boy of 15 kg sits on the other end. If they are separated by 4 m , how far from the boy the centre of mass situated. Neglect the weight of the see saw.

Let the equilibrium is at a distance a meter from boy =>it is (4 - a) meter from the 45 kg person So m1r1=m2r2 =>a x 15 = (4 - a) x 45 =>15a = 180 - 45a =>60a = 180 =>a = 180/60 = 3 meter Therefore the centre of mass of body will be situated 3m away from the boy

Let the equilibrium is at a distance a meter from boy
=>it is (4 - a) meter from the 45 kg person
So m1r1=m2r2
=>a x 15 = (4 - a) x 45
=>15a = 180 - 45a
=>60a = 180
=>a = 180/60 = 3 meter
Therefore the centre of mass of body will be situated 3m away from the boy