Speed Flashcards
How do you work out distance?
Speed X Time = Distance
How do you work out speed?
Distance / Time = Speed
/ = divided by
How do you work out time?
Distances / Speed = Time
/ = divided by
What is speed?
Speed is a way of saying how fast or slow something is moving
If the units for distance are meters and the units for time is seconds, what is the units for speed?
The units for speed will be meters per seconds (m/s)
How do you work out the speed?
Speed = distance / time
If the gradient line is steep, what does this mean for the speed of a car?
The steeper the gradient line the faster the car
How do you work out the gradient?
To work out the gradient you first work out how many seconds there are per box in the chart
When an object falls through the air what two forces does it experience?
When an object falls through the air it experiences two forces, weight and air resistance
As an object falls initially how does the weight relate to the air resistance?
As an object falls initially the weight is much greater than the air resistance
What happens to an object as it falls to make it stop accelerating?
As the object speeds up the air resistance gets bigger until the two forces are equal. At this time, the forces are balanced and the object stops accelerating.
What is the speed triangle?
/ \ / D \ \_\_\_\_\_ /S x T\ ------
On a speed time graph what is the area under the graph?
On a speed time graph the area under the graph = distance
If a speed time graph has a positive correlation what does it show the vehicle is doing
It shows the vehicle is accelerating
If the speed time graph has a gradient of 0 {flat} what does it mean the vehicle is doing?
It shows the vehicle is stationary or at a constant speed
If the speed time graph has a negative correlation what does this mean for the vehicle?
It means the vehicle has a negative correlation
What is terminal velocity?
Terminal velocity means the object can’t go /fall/ any faster
What is the mean speed?
Mean speed is the average speed the object travels at across the entire distance
What is a wind tunnel?
A wind tunnel is when you send a stream of smoke over a car and see the line that it takes to see how much resistance there is
If there is a lot of air {force} hitting an object, how does it effect the speed of the object and why?
The amount of air {force} hitting the object, the higher the area of the object must be, so the higher the pressure, meaning the slower he object goes
What is turbulence?
Turbulence is the disturbance in the pattern of air
If an object has high resistance and is slow then what happens to the turbulence?
This means the turbulence is higher
Give four examples of streamlined objects
Rugby balls
Bullets
Knives {throwing}
Swords
Darts
CoatsWhy do we streamline objects?
We streamline objects to reach maximum speed with minimum effort
What is air resistance caused by?
Air resistance is caused by force across an area
How does speed affect air resistance?
^ Speed Increase in speed means
^ distance / time an increase in distance over time means
^ air particles collide more air particles collide, meaning
^ FoRcE a higher force
^ area {which is higher if the area is higher}
^ pressure meaning more pressure, also meaning
^air pressure there is higher air resistance
What causes resistance?
Collision with particles causes resistance
