Question

Which of the following has more inertia______
A. $5{\text{Rp}}$ coin and ${\text{2Rp}}$coin
B. ${\text{2Rp}}$ and ${\text{3Rp}}$coin
C. Ten kilogram iron
D. None of these

Answer 1

Hint: In this question use this concept that the quantity inertia totally depends upon the mass of an object.

Complete step-by-step answer:

Inertia is Newton's first law of motion which is defined as the tendency of an object to keep moving at a constant speed in a straight line or will be in the resting state until and unless an external force is applied on it or we can say that it is the resistance of any physical object to any change in its velocity which include the direction of motion or change in object's speed.
And inertia simply depends upon the mass of an object means as the mass of an object increases inertia will increase and also if mass is less than inertia is also less.

In this question three cases are given, first is $5{\text{Rp}}$ coin and ${\text{2Rp}}$coin, second is ${\text{2Rp}}$ and ${\text{3Rp}}$coin and third is ten kilogram iron.
So it's clear that ten kilogram iron has more mass as compared to the rest of the two cases therefore its inertia is more.

Hence the correct option is C i.e. ten kilogram iron.

Note: Inertia is basically of three types first is inertia of rest according to which an object rests where it is placed and it will rest there until and unless we apply an external force, second is inertia of motion in which an object will continue to move at the constant speed until an external force acts on it and third is inertia of direction in which the object will continue to keep on moving in the same direction until and unless an external force is applied on it.