Chapter 1.2, Problem 13SSC

Interpretation Introduction

Interpretation:  The difference in mass and weight on the moon as compared to on earth needs to be explained.

Concept introduction:  Mass is usually told that how much matter is present in the object. It is measured in kilograms, pounds, grams, ounces or tones, etc. It does not change with the location.

Weight is the measure of the stretch of gravity on an object. It is measured by a different scale. It does change with change in the location of an object due to change in gravitational force.

Answer to Problem 13SSC

The mass would be the same, but the weight would be 1/6 on the Earth because the force due to gravity is one-sixth that of Earth.

Explanation of Solution

The mass is constant on the moon because it does not change with the location.

The gravity of the moon is much less than the gravity of the Earth.  

The weight depends on the gravitational force, which changes with the change in location. The weight is less on the moon as compared to the earth.

If the weight of a human is 99 Pounds on the Earth, the human will weigh much less on the moon. The gravity force on the moon is approx one-sixth as compared on Earth. So, the weight of a human on the moon will be approx 16.4 pounds that is 1/6^th of 99 pounds.

Conclusion

The force due to gravity on moon is one-sixth (1/6) that of Earth, so the weight on the moon would be 1/6 of the weight on the Earth. The mass remains the same on the moon because the quantity/ amount of matter do not change.