Speed Flashcards
How do you work out the distance travelled
Speed X time
How do you work out the time taken for a travelling object
Distance/speed
How would you calculate distance of an object that is changing speed
Distance=average speed X time
Find the average speed (adding speeds and dividing by the amount of speeds object is changing by)
What is distance measured in
Metres (m)
On distance-time graphs how can speed be calculated
By the gradient
The steeper the gradient, the faster the speed
What is time taken measured in
Seconds (s)
What is average speed measured in
Metres per second (m/s)
How do you work out the speed of any moving object
The distance it travels/Time taken to travel that distance
The faster the object the shorter time it takes to travel a particular distance
How do speed cameras work
First picture is taken of a vehicle
A second is taken shortly after
Position of vehicle in relation to distance markings on the road in the two pictures calculates speed
What do slopes of distance-time graphs represent
If the slope is steep what does this mean
The speed of an object
The steeper the slope the faster the speed
On a speed-time graph what does a slope represent
The acceleration
The steeper the slope the bigger the acceleration
On Speed-time graphs
How does constant acceleration gradually increase
Increases at a uniform rate
(Speed-time graphs)
What does a negative gradient slope indicate
Deceleration
(Speed-time graphs)
How can acceleration be calculated
Working out the gradient in different parts of the graph
The steeper the gradient the bigger the acceleration
What does the area under a speed-time graph show
Distance travelled
How do you work out relative velocity
Relative velocity= velocity 1 - velocity 2
What is acceleration measured in
Metres per second per second (m/s2)
How do you calculate acceleration
Change in speed (m/s) / Time taken for this change in speed (s)
If we need to note the direction an object is moving in we use what
Velocity
It is speed given in direction
When two objects move in opposite directions at the same speed their velocities have the same magnitude but opposite signs
What happens when a force acts in a different direction to which the object is moving
The object changes direction and acceleration occurs
What is acceleration a measure of
What would give a bigger acceleration
Change in speed per second
A meaure of how quickly an object speeds up or slows down
Greater change in speed gives a larger acceleration
