Motion and forces Flashcards
describe a scalar quantity
It has a magnitude (size) but no specific direction
describe a vector quantity
It has a magnitude (size) and a direction
name 5 vector quantities
- Displacement
- Velocity
- Acceleration
- Momentum
- Force
(Lift Drag Thrust Weight)
name 5 scalar quantities
- Length
- Area
- Speed
- Volume
- Mass
(Density, Pressure, Temp, Energy, Direction ,Power)
define velocity
Speed in a stated direction
What is the typical walking speed of a person?
1.5 m/s
What is the typical running speed of a person?
3 m/s
What is the typical speed of cycling?
6 m/s
what the typical speed of sound?
330 m/s
what are things that affect the thinking distance?
- drugs
- fatigue
- alcohol
What are things that affect the braking distance?
- weather
- condition of the road
- condition of the vehicle
What is the gradient on a distance - time graph?
speed
What is the gradient on a velocity - time graph?
acceleration
How do you find the distance on a velocity - time graph?
find the area
What are the steps of carrying out the Light Gate experiment?
1.Set up the light gates a set distance apart
2. make sure that the card on the trolley passes through the light gate
What is the acceleration in free fall?
10m/s
What is Newton’s First Law?
velocity of an object is stationary unless there is a force acting on it
What is Newton’s Second Law?
The idea that the acceleration of an object is directly proportional to he resultant force acting on it
What is Newton’s Third Law?
The forces on interacting objects are equal and opposite
Collisions : what is the purpose of seatbelts?
To get more time to change momentum.
Smaller rate of change of momentum = lower force
what is the stopping distance made up of?
Thinking distance + Braking distance
What is the stopping distance affected by?
1.mass of the vehicle
2.speed of the vehicle
3.the driver’s reaction time
4.the state of the vehicle’s brakes
5.the state of the road
6.the amount of friction between the tyre and the road surface
what’s circular motion?
an object moving in a circular orbit has a constant speed and a changing velocity as the direction changes
what’s the thinking distance?
time taken to react and apply the brake
what’s the braking distance?
time taken from brake being applied to reaching a stationary motion
what effects the thinking distance?
tiredness
alcohol
drugs
old age
fog
why do icy roads effect the braking/stopping distance?
-when the vehicle touches the ice, the tyres slip up and you just drive slower
-driver may not see ice and panic once they feel it
