AQA Physics paper 2

AQA Physics paper 2 1. force - - this can change something's speed, direction, or shape a. it can be push/repulsive or pull/attractive 2. vector - a quantity with magnitude (size) AND direction 3. scalar - a quantity with magnitude (size) but NOT direction 4. examples of vectors - force, weight, velocity, acceleration, displacement 5. examples of scalars - distance, mass, speed, energy, time 6. contact forces - occur when an object is supported by or strikes another object e.g. friction 7. non-contact forces - the objects don't physically come into contact, e.g. gravity, magnetic force 8. mass - the measure of the amount of matter that anything (including people) are made up of (this is a scalar) 9. weight - the measure of the force on an object due to gravity (gravity has a direction, towards the centre of the Earth, so this is a vector) 10. the Earth's gravity - 9.81m/s² (approx.) - it is in m/s² because gravity refers to the acceleration that is put on objects as they are pulled in 11. weight - = mass X gravity (can be rearranged) - (also, gravity will always be 9.81 on Earth (above)) 12. gravity ideas on the moon and Earth - - the gravity of the moon is less than on Earth as the moon has less mass than the Earth a. one would weigh less on the moon than on Earth, but still have the same mass b. there is no air resistance on the moon as there is no air, so two objects dropped simultaneously, regardless of their weight/mass, would hit the ground simultaneously, as there is no force working against gravity