Section 1 Flashcards
(28 cards)
where is tension found?
in a rope
friction is found between road surfaces which are…
slipping past each other
what is friction?
a force that opposes motion
how to investigate motion
- toy car on a ramp
- light gate
describe how objects reach terminal velocity
- first set off= much more force accelerating them than slowing them down
- as velocity increases, resistance increases
- acceleration gradually reduces until the resistance force is equal ti the accelerating force§
downwards force on skydiver
weight
upwards force on skydiver
resistance
how to investigate falling objects
- sycamore seeds
- measure mass and area
- time how long they take to reach the ground
a bigger force means a…
greater acceleration or deceleration
a bigger mass means a…
smaller acceleration
unbalanced force=
resultant force
Newton’s third law
if object A exerts a force on object B, then object B exerts the exact OPPOSITE force on object A
vectors
have size and direction
scalar quantaties
have only size
vector quantaties:
- force
- velocity
- displacement
- acceleration
- momentum
scalar quantaties:
- mass
- temperature
- time
- length
the thinking distance is affected by:
- how fast you’re going
- tiredness, drugs, alcohol
the braking distance is affected by:
- how fast you’re going
- the mass of the vehicle
- the quality of the brakes
- how good the grip is
momentum before=
momentum after
crumple zones
- crumple on impact
- increasing the time taken for the car to stop
seat belts
- stretch slightly
- increasing the time taken for the wearer to stop
- this reduces the force acting on the chest
air bags
-slow you down more gradually
what is a moment?
the turning effect of a force
where is the centre of gravity?
directly below the point of suspension
