5.2 Weight,mass And Gravity Flashcards
What does gravity do ?
It attracts all masses
What are two important effects of gravity ?
On the surface of a planet ist makes all things fall towards the ground
Gives everything a weight
What is mass ?
The amount of ‘stuff’ in an object
What is the value of mass anywhere ?
The mass is the same value anywhere in the surface ?
What is weight ?
The force acting on an object due to gravity
What affects the value of weight ?
The gravitational field
How does weight vary with location ?
Because the gravitational field strength varies with location.
How does the gravitational field strength vary?
Stronger the closer you get to the mass causing the field and
Stronger form large masses
Where should you think the force weight should act on ?
A single point on the object (centre of mass) where the whole mass is concentrated
On a uniform object where is the centre of mass ?
At the centre of the object
What can weight be measured with ?
Calibrated spring balance (Newton meter)
How do you calculate the weight of an object ?
Weight = mass(kg) x gravitational field strength (n/kg)
What is the relationship between mass and weight ?
Weight is directly proportional too mass