| what is a scalar quantity | a quantity which has only magnitude |
| what is a vector quantity | a quantity which has both magnitude and direction |
| give six examples of vector quantities | displacement
velocity
acceleration
force
weight
momentum |
| when do vector quantities change | when magnitude and/or direction changes |
| the equations of motion relate to which 5 quantities? | suvat
displacement
initial velocity
final velocity
acceleration
time |
| name the four equations of motion - used when 3/5 suvat quantities are known | v=u+at
s=ut + 1/2at²
v²=u² +2as
s=1/2(u+v)t |
| when do we use suvat equations | when considering objects that move with uniform (constant) acceleration |
| when working with vectors, what must be done with vectors going in opposite directions | give vectors going in opposite directions opposite signs
(time can't be negative) |
| if a motion question states from rest what information about the equations is being given? | initial speed = 0
u = 0 |
| if a question states freely under gravity what information about the equations is being given? | acceleration is ±9.8 metres per second due to gravity |
| at its maximum height, what speed is an object? | 0 metres per second |
| what does the gradient of a displacement time graph give | the velocity of the object at that time |
| what does the gradient on a velocity time graph give | the acceleration of the object at that time |
| what does the area under a velocity time graph give | the displacement |
| what are the corresponding acceleration-time and displacement-time graphs for this vt graph | ... |
| what are the corresponding s-t and a-t graphs for this v-t graph | ... |
| what are the corresponding s-t and a-t graphs for this v-t graph? | ... |
| describe an experiment to measure the acceleration of an object down a slope | with the following equipment:
two light gates
timer
trolley carrying a mask (piece of card) of a known length
Set up apparatus so the trolley runs down the slope and the mask on the trolley cuts the beams of both light gates.
take the measurements: length of mask, time to cut first light gate, time between light gates, time to cut second light gate
Calculate initial and final velocity and sub into the formula a=v-u/t |
| describe the experiment to measure the acceleration of an object using a double mask | measure width of the two pieces of card attached to the trolley
Place a light gate at the bottom of the slope and release the trolley.
Light gate measures time taken for first card to pass through the beam. Use this to calculate initial speed. (d=vt)
Do the same for the second card to find final speed.
Light gate measures time taken for both cards to pass through the light gate.
use a=v-u/t to calculate the acceleration. |
