Question

What is the mass and weight of an object on the surface of the moon, if on the earth its mass is $12\,kg$.

Answer 1

To solve this type of question one must have a concept of mass and weight then you can easily solve the question. First here we will find the mass of the object on the surface of the moon and then by applying formula we will find the weight of the object on the surface of earth and then applying the concept we will find the weight of the object on the surface of the moon.

Formula used:
$W = mg$
Where, $W$ is weight, $m$ is mass and $g$ is the acceleration due to gravity.

Complete step by step answer:
As per the question the mass of the object given on earth is $12\,kg$. As we all know that mass is something that never changes and is not affected by gravity. So, we can say that the mass of the object on the moon will be the same as on earth i.e., $12\,kg$. Now we have to calculate the weight of the object on the moon and we know that weight is nothing but the product of mass and gravity. So, first the weight of the object on earth will be:
$W = mg$
$\Rightarrow W = 12 \times 9.8 \\\ \therefore W = 117.6\,N$
And as per question we have to find the weight on the moon and we know that on the moon the weight is $\dfrac{1}{6}$ that of earth. Therefore, we can say that the weight on the moon is $\dfrac{{117.6}}{6} = 19.6\,N$.

Hence the mass and weight of an object on the surface of the moon, whose mass is $12\,kg$ on earth, will be $12\,kg$ and $19.6\,N$ respectively.

Note: We must remember that the mass of an object/body is a universal constant and never changes at any place in the universe. And for the calculation of the weight of an object/body, we must keep in mind that the weight of the object or body on the moon is one-sixth of the weight on the earth.