Forces and Motion Part 1 Flashcards
Unit for mass
Kilograms (kg)
Unit for length
Metres (m)
Unit for force
Newtons (N)
Unit for time
Seconds (s)
Equation to calculate average speed
average speed = total distance travelled/total time taken
Symbol equation to calculate speed
v=d/t
Steeper line on distance/time graph
Object is moving faster
Straight line on acceleration/time graph
Steady speed
Curve getting steeper on acceleration/time graph
Accelerating
Curve getting shallower on acceleration/time graph
Decelerating
First step to find speed using a distance/time graph
Determine gradient
Equation to find gradient
Gradient = Change in distance/Change in time
Forces: Vector or scalar
Vector
Magnitude and direction
Scalar quantities
Only have magnitude eg temperature
Examples of forces
Air resistance, friction, weight, thrust, magnetic, gravitational
Representing forces using arrows
Ruler, pencil
Head shows direction
Size shows moment
Balanced forces
ZERO resultant force
Object remains stationary or moves at constant speed
Unbalanced forces
Resultant force
Object accelerates or decelerates
Friction
Measure it by measuring force needed to overcome
More mass, more friction
Equation to find stopping distance
Stopping distance = thinking distance + braking distance
Reaction time can be affected by
Tiredness Distractions Alcohol Drugs Speed
The longer the reaction time, the …… the thinking distance
Longer
Braking distance can be affected by
Road conditions Weather Condition of vehicle Mass in vehicle Speed
Fixed point
Pivot/fulcrum
Turning effect
Moment
equation for moment
Moment = force * perpendicular distance
M=Fd
Principle of moments
Object in equilibrium if Mcw = Macw
Equation for weight
Weight =mass * gravitational pull
W=mg
