(a) A boy is of mass $40 k g$ . If the pull of gravity on $1 k g$ on the surface of earth is $9.8 N$ and at the surface of moon is $1.6 N$ , find (i) the weight of boy at the earth's surface, (ii) mass and weight of the boy at the moon's surface.

(b) State three differences between mass and weight.

Open in App

Solution

(a) Given : Mass of the boy $= 40 k g$

(i) At the earth's surface,

Weight $= 40 k g f$

Since $1 k g f = 9.8 N$ ,

Weight $= 40 \times 9.8 N = 392 N$

(ii) At the moon's surface

Mass of boy will remain same as at the earth surface $= 40 k g$

But $1 k g f = 1.6 N$

so weight $= 40 \times 1.6 N = 64 N$

(b)

Suggest Corrections

Similar questions

Q. The weight of a body of mass

6.0 k g

on moon is

10 N

. If a boy of mass

30 k g

goes from earth to the moon surface, what will be his

(a)

mass,

(b)

weight?

The mass of a boy is 40 kg. What is his weight on the surface of the earth and what is his weight on the surface of the moon? Given that g_e = 9.8 ms^-2 and g_m = $\frac{1}{6}$ g_e.

The earth attracts a body of mass $1 k g$ with a force of $10 N$ . The mass of a boy is $50 k g$ . His weight will be :

Q. The weight of a boy on the surface of the moon is

300 N

. The weight of this boy on the surface of earth is :

Calculate the weight of a boy of mass 50 kg on Earth's surface. (Use g = 10 m/s²)

Join BYJU'S Learning Program

(a) A boy is of mass 40 kg. If the pull of gravity on 1 kg on the surface of earth is 9.8 N and at the surface of moon is 1.6 N, find (i) the weight of boy at the earth's surface, (ii) mass and weight of the boy at the moon's surface. (b) State three differences between mass and weight.

(a) Given : Mass of the boy =40 kg (i) At the earth's surface, Weight =40kgf Since 1kgf=9.8 N, Weight =40×9.8 N=392 N (ii) At the moon's surface Mass of boy will remain same as at the earth surface =40 kg But 1kgf=1.6 N so weight =40×1.6 N=64 N (b)