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27 Cards in this Set
- Front
- Back
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Formula for speed
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Speed (metres/second, m/s)
= distance travelled (metres, m) ------------------------------- time taken (seconds, s) |
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Define speed
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The speed of an object describes the rate at which it is travelling
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Define velocity
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The velocitu of an object is both it's speed and direction
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Define acceleration
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The rate at whioch an objects velocity is changing
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Formula for acceleration
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Acceleration (m/s²)
= Change in velocity (m/s) ------------------ Time taken for change (s) |
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When acceleration and velocity are in the same direction does the object speed up or down
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Speeds up
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When acceleration and velocity are in opposite directions does the object speed up or down
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The object slows down
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the steeper the slope of a distance time graph, the greater the ......
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speed it represents.
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The steeper the slope of a velocity time graph the greater the .....
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acceleration it represents.
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The area under a velocity time graph represents what.
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The distance travelled.
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Newtons third law of motion states
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Whenever two objects exert forces on each other, the forces are equal in size and opposite in direction
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When forces cancel each other out we say they are ...
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balanced
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Do balanced forces affect an object's motion
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No
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Do unbalanced forces affect an object's motion
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Yes; depending on the direction of the unbalanced force it may cause the object to speed up, slow down or change direction
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The greater the size of the unbalanced force on an object the greater it's ...
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acceleration
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The bigger the mass of an object the ...... the unbalanced force that is needed to give it a particular acceleration
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larger
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Acceleration is proportional to ....
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force
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Newtons second law of motion
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force
= mass x acceleration |
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One newton will accelerate a mass of one kilogram at a rate of ....
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one metre per second²
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Frictional forces ten to make a moving object ....
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slow down
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What does the braking distance of a vehicle do if its speed increases
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The braking distance increases
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What are the two parts of a stopping distance
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thinking
breaking |
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what is the breaking distance
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the distance the vehicle travels while the breaks are applied
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What is the reaction time
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Thinking distance - the time travelled by the vehicle in the time between the driver knowing the brakes should be applied and actually applying them
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Stopping distance =
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Thinking or reaction distance + braking distance
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Stopping distance increases if;
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the road is wet or icy;
the driver is tried or under the influence of drink or drugs; the vehicles brakes or tyres have been pororly maintained; the vehicles spped before applying the brakes is greater |
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Weight =
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mass x gravitational field strength
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