Paper 1 Fully Assessed topics Flashcards
what does a distance-time graph show?
how far something had travelled.
what does the GRADIENT on a distance-time graph show?
the gradient at any point gives the SPEED of the object.
what do the FLAT SECTIONS on a distance-time graph show?
show where the object has stopped moving.
what does a STEEPER GRADIENT on a distance-time graph show?
means the object is going faster.
what does a CURVE on a distance-time graph show?
curves represent acceleration.
what does a CURVE GETTING STEEPER on a distance-time graph show?
a curve getting steeper means its speeding up. (increasing gradient)
what does a LEVELLING OFF CURVE on a distance-time graph show?
a levelling off curve means its slowing down. (decreasing gradient)
how do you work out the speed from a DISTANCE-TIME graph?
speed of a section = gradient = change in y/change in x
OR for average speed divide total distance travelled by time it takes.
average speed (velocity)
average speed = distance moved / time taken
what is the difference between speed and velocity?
- speed is just how fast you’re going (e.g. 30 mph or 20 m/s) with no regard to the direction
- velocity however must also have the direction specified (e.g. 30 mph north or 20 m/s 060 degrees.)
- this means you can have objects travelling at a constant speed with a changing velocity. this happens when the object is changing direction whilst staying at the same speed.
what is acceleration?
- how quickly velocity is changing.
- this change in velocity can be a change in SPEED or a change in DIRECTION or both.
what is the unit for acceleration?
m/s2
what are the 2 formulas for velocity?
- a = change in velocity / time taken
a = (v-u)/t - 𝑣^2=𝑢^2+2𝑎𝑠
v is final velocity, u is initial velocity, and s is distance travelled when accelerating
what does a velocity-time graph show?
how an object’s velocity changes over time.
what does the GRADIENT on a velocity time graph show?
gradient = ACCELERATION.
what do the FLAT SECTIONS on a velocity time graph show?
flat sections represent STEADY SPEED.
what does the STEEPNESS of a velocity time graph show?
the steeper the graph, the greater the acceleration or deceleration.
what do the UPHILL SECTIONS on a velocity time graph show?
uphill sections (/) are acceleration
what do the DOWNHILL SECTIONS on a velocity time graph show?
downhill sections () are deceleration.
what does the AREA UNDER THE GRAPH on a velocity time graph show?
the area under any part of the graph is equal to the DISTANCE TRAVELLED in that time interval
what does a CURVE on a velocity time graph show?
a curve means CHANGING ACCELERATION
practical: investigating the motion of a toy car on a ramp. METHOD
- set up your apparatus like in this diagram, holding the car still just before the first light gate.
- mark a line on the ramp - this is to make sure the car starts from the same point each time.
- measure the distance between each light gate - you’ll need this to find the car’s average speed.
- let go of the car just before the light gate so that it starts to roll down the slope.
- the light gates should be connected to a computer. when the car passes through each light gate, a beam of light is broken and a time is recorded by data logging software.
- repeat this experiment several times and get an average time it takes for the car to reach each light gate.
- using these times and the distances between light gates you can find the average speed of the car on the ramp and the average speed of the car on the runway.
- using light gates means you don’t get any timing errors as a result of a person reacting slowly.
practical: investigating the motion of a toy car on a ramp. EXPERIMENTING.
- you could try seeing if the mass of the car affects its average speed - just load weights onto it.
- to see how friction affects the motion of the car you could try placing different materials on the ramp. if you do this, make sure they’re laid flat and they don’t change the angle of the ramp in any way.
- you could investigate the acceleration of the car due to gravity by starting it off higher off the ramp and seeing how this affects its average speed.
- you could change the angle of the ramp to see how it affects the speed.
- you could even try with different cars - see how the size, shape and weight of the car affects the speed.
how does friction affect objects?
- if an object has no force propelling it along, it will always slow down and stop because of friction (unless you’re in space).
- friction is a force that OPPOSES MOTION.
- to travel at a steady speed, things always need a driving force to counteract the friction.