Question

The weight of an object:
A. Is the quantity of the matter it contains.
B. refers to its inertia.
C. is the same as its mass but is expressed in different units.
D. is the force with which it is attracted to the earth.

Answer 1

Hint: There are majorly two types of quantities, scalar, and vector quantities. All the quantities are divided into these two categories. Scalar quantities are those quantities, which have only magnitude eg – mass, speed, pressure, etc. Vector quantities are those which have both magnitude and directions eg – weight, velocity, and thrust. For instance, speed is a scalar quantity and velocity is a vector quantity.

Complete step-by-step solution:
The quantity of matter present within a defined space is called mass. This quantity is universally the same at every place. That means it is the same if we go to the moon or Saturn. Also, the inertia of the body is the measure of the mass of the body and not its weight.
Also mass is a scalar quantity whereas weight is a vector quantity. Hence they can’t be the same.
Now, as we know that every planet has its own gravitational pull by the virtue of which it attracts every object lying on or near the surface of the earth. This force has the name of gravity. It's S.I. unit is Newton ‘N’. It is the function of gravity at a place and hence it is variable from place to place. For example, if the weight of a body is 600 N on the surface of the earth then the weight of the same body will be 100 N on the surface of the moon.
The weight, mass, and acceleration of gravity are related by the relation: $W=mg$. Thus, option D. is correct.

Note: Sometimes students neglect the difference between vector and scalar quantity. But this is a very huge mistake. The student should always be aware of the vector quantities and the directions associated with it. For example, weight is a type of force, which is a vector quantity and its direction is towards the center of the earth at every place on earth.