Question

An astronaut weighs 104 Newton’s on the moon where the strength of gravity is 1.6 Newton’s per kilometer watch is her mass

Answer 1

Weight, mass and gravity

People often confuse mass and weight. Remember that weight is a force, and is measured in newtons. Mass is measured in kilograms (kg).

Mass

The mass of an object is the amount of matter or "stuff" it contains. The more matter an object contains, the greater its mass. An elephant contains more matter than a mouse, so it has a greater mass. Mass is measured in kilograms, kg, or grams, g.

A 100 kg object has a greater mass than a 5 kg object. Remember an object's mass stays the same wherever it is.

Gravity

All objects have a force that attracts them towards each other. This is called gravity. Even you attract other objects to you because of gravity, but you have too little mass for the force to be very strong.

Gravitational force increases when:

the masses are biggerthe objects are closer

Gravity only becomes noticeable when there is a really massive object like a moon, planet or star. We are pulled down towards the ground because of gravity. The gravitational force pulls in the direction towards the centre of the Earth.

"Down" is towards the centre of the Earth, wherever you are on the planet

Weight

Weight is a force caused by gravity. The weight of an object is the gravitational force between the object and the Earth. The more mass the object has the greater its weight will be.

Weight is a force, so it's measured in newtons. On the surface of the Earth an object with a mass of 1 kg has a weight of about 10 N