Speed

Question 1

what does average speed means

Answer 1

is the total distance travelled divided by total time taken ( an object may not actually travel at that speed at any point in its journey)

Question 2

what does instantaneous speed means

Answer 2

is the speed of a moving object at any particular instant in time

Question 3

how do you measure average speed

Answer 3

• measure a distance with a trundle wheel
• measure the time taken to travel this distance with a stop clock
• calculate the average speed

Question 4

how do you measure instantaneous speed

Answer 4

• Attach a piece of card to the car.
• Measure the length of the card with a ruler.
• Measure the time taken for the car to pass the point using a light gate connected to a stop clock.
• Calculate the instantaneous speed

Question 5

what is the formula for instan. speed

Answer 5

v=d/t

Instantaneous speed = length of card .
time through light gate

Question 6

what is the formula for average speed

Answer 6

Average speed = Total distance

Total time Time

Question 7

describe constant speed

Answer 7

a straight line from a speed point eg. 40m/s

Question 8

describe constant acceleration from rest

Answer 8

a diagonal line from 0 to 40m/s

Question 9

describe constant deceleration

Answer 9

a diagonal line from 40 to 0m/s

Question 10

what happens to the number for a deceleration calculation

Answer 10

it has a negative answer

Question 11

describe constant acceleration from 20m/s

Answer 11

a diagonal line from 20 to 40m/s

Question 12

how do you measure a distance travelled by a moving object

Answer 12

by calculating the area under a speed time graph