Question

Two small objects of masses 100 g and 200 g
possess velocities 10 m/s and 10j m/s
respectively. The velocity of their centre of mass
(in m/s) is
(1) 207
(3) 7 3 1 + 2
(4) 107​

Answer 1

Answer:

Let the masses of the small objects be denoted as “m₁” g & “m₂” g respectively and their velocities be denoted as “v₁” m/s & “v₂" m/s respectively.  

Masses of two small objects are given as:

m₁ = 100 g = 100/1000 kg = 0.1 kg

m₂ = 200 g = 200/1000 kg = 0.2 kg

and,

The velocities of the two small objects are given as:

v₁ = 10i m/s

v₂ = 10j m/s

The centre of mass is a point where the entire mass of the system is concentrated. The formula for calculating the velocity of the centre of mass is given as = [(m₁v₁ + m₂v₂) / (m₁ + m₂)].

Thus,

The velocity of centre of mass  is,

= [{0.1*(10i)} + {0.2*(10j)}] / [0.1+0.2]  

= [1i + 2j] / 0.3 m/s

= [{i + 2j}/0.3] m/s