Forces: Gravity Flashcards
Why is gravity a vector quantity?
Gravity is a vector quantity because it has direction and magnitude.
What actually is mass?
Is mass a scaler or vector quantity?
Mass is how much matter an object has within it. (Kg)
Mass is a scaler quantity as it has magnitude but no direction.
What is weight?
Weight is the force acting on an object due to gravity.
What can we use to determine the weight of an object?
To determine the weight of an object we can use a calibrated spring-balance / newton-meter.
The weight of an object and the mass of an object are directly
proportional.
This means if we double the mass, the weight also doubles.
The mass of an object is same everywhere, the weight is not.
An elephant which has a mass of 1000kg will still have a mass of 1000kg on the moon.
What is actually meant by the gravitational field strength?
The gravitational field strength is a measure of the force of gravity in a particular location.
What is the “centre of mass”?
The “centre of mass” is the weight of an object (force due to gravity) which is considered at a single point.
Why is gravity a non-contact force?
Gravity is a non-contact force because the two objects do not need to be touching.
(a raised pen in the air will still fall without touching the earth)
