Motion

Question 1

What is motion?

Answer 1

Motion is the change in position.

Question 2

What is speed?

Answer 2

Speed is the rate at which an object covers distance.

Question 3

Is speed a scalar or a vector?

Answer 3

Scalar.

Question 4

What is the formula for speed?

Answer 4

Speed = distance/time

Question 5

What is average speed?

Answer 5

Speed is not constant and changes over time, therefore the average speed of a specific distance is calculated.

Question 6

What is the formula for average speed?

Answer 6

Average Speed = total distance/total time

Question 7

What is acceleration?

Answer 7

Acceleration is the rate at which speed changes.

Question 8

What is the formula for acceleration?

Answer 8

Acceleration = change in speed/change in time

Question 9

What 3 things do we need to calculate acceleration?

Answer 9

1. Initial speed
2. Final speed
3. Time taken

Question 10

What is initial speed?

Answer 10

Initial speed is the speed at the start of the acceleration process.

Question 11

What is final speed?

Answer 11

Final speed is the speed at the end of the acceleration process.

Question 12

What is the formula to calculate the change in speed?

Answer 12

Final speed - Initial speed

Question 13

What is the SI unit for acceleration?

Answer 13

Metres per second squared (Metres per second per second)

Question 14

Here is an example of an acceleration question. Pete drives a car on a highway. He wants to pass a truck that is ahead of him. so he accelerates. His initial speed is 100km/h. He drives for 5s and his final speed is 140km/h. What is his acceleration?

Answer 14

Final speed - initial speed
____________________
change in time

= 140-100
  \_\_\_\_\_\_\_
       5
= 40
    \_\_\_
      5
= 8 metres per second squared

Question 15

What is deceleration?

Answer 15

Deceleration is negative acceleration, because an object is slowing down, not speeding up.

Question 16

Here is an example of an deceleration question. Pete drives a car on a highway. He is driving at 120km/h when he sees a truck up ahead, and slows down to 80km/h in 4s. What is his deceleration?

Answer 16

Final speed - initial speed
____________________
change in time

= 80-120
   \_\_\_\_\_
      4
=   -40
    \_\_\_\_
       4
= -10 metres per second squared