Unit2 Lesson2 Flashcards
Weight and Mass
What is Weight?
- Weight is the force of gravity on an object.
- Weight = Gravity x Mass
- It’s a force measured in Newtons.
Why your weight will vary between earth, the moon and space?
Because weight depends on gravity.
Why weight CAN change?
An object’s weight is a measure of the pull of gravity. Weight CAN change depending on your location on Earth, in the Solar System, or in the Universe.
As you travel away from the Earth’s surface, your mass stays the same, but your weight reduces as gravitational pull decreases as you go further out into space.
Did you know your weight changes depending on where you are on Earth!
The gravitational pull of Earth on you can change slightly as you move around the surface of the Earth. This is because the Earth is not a perfect sphere and your distance from Earth’s center can change. Therefore, generally speaking your weight is lower on top of a mountain than at sea level.
How is your weight in the universe?
Your weight is a measure of the pull of bravity between you and the body (planet) you are standing on. Your weight depends on the gravitational pull of the celestial object. So the greater the gravity greater your weight.
What is Mass?
- Mass is a measure of the amount of matter in an object.
- Mass is a combination of the total number of atoms, and the type of atoms in an object.
- An object’s mass does not change unless you remove some!
Are mass and weight same?
Mass and weight are used to mean the same thing on Earth and we often say that an object weights a certain amount of kg. That’s because gravity is more or less the same all over the earth, buth weight should be measured in newtons since it’s a force.
Gravity on Earth?
Gravity is 9.8 N/kg on Earth.
Mass on Earth = 100kg
Weight = 100 (kg) x 9.8 (N/kg) = 980 N
Gravity on Moon?
Gravity on the moon is 1/6th that of earth, 1.6 N/kg.
Mass on Moon = 100kg
Weight on Moon = 100 x 1.6 = 160 N
Gravity in space?
There is no gravity in space.
Mass in space = 100 Kg
Weight = 100 x 0 = 0 N
