Speed
Distance-Time Graphs
Acceleration
Speed-Time Graphs
Exam Questions
100
What is the unit for speed?
ms-1
100
What does a diagonal line on a distance-time graph mean?
Constant speed
100
What is the unit for acceleration?
ms-2
100
What do these 3 shapes of a speed-time graph represent?
Upward diagonal line
Horizontal line
Downward diagonal line
Upward diagonal line = Accelerating (speeding up)
Horizontal line = Constant speed
Downward diagonal line = Decelerating (slowing down)
100
2021 Exam (Question 1a) - DOUBLE POINTS
Describe the motion in sections A, B, C and D
Section A: Accelerating / speeding up
Section B: Constant speed
Section C: Decelerating / slowing down
Section D: Stopped
200
v=(/_\d)/(/_\t)
In the formula above, what do the 3 variables represent?
v = Speed
/_\d = Change in distance
/_\ t = Change in time
200
What does a curved line on a distance-time graph mean (upward and downward)
Accelerating & decelerating
200
a=(/_\v)/(/_\t)
In the formula above, what do the 3 variables represent?
a = Acceleration
/_\v = Change in speed
/_\ t = Change in time
200
What is the gradient of a speed-time graph equal to?
Acceleration
200
2021 Exam (Question 1d) - DOUBLE POINTS
Another race is 3,000 m long. Zoi averaged a speed of 5 ms-1. Calculate the time it would take her to finish the race. Show all working
t=(/_\d)/(v)
t=(3000 m)/(5 ms^(-1))
t = 600 seconds
300
v=(/_\d)/(/_\t)
Rearrange the above formula so that time becomes the subject of the equation (t = _______)
t=(/_\d)/(v)
300
What is the gradient on a distance-time graph?
Speed
300
a=(/_\v)/(/_\t)
Rearrange the above formula so that speed becomes the subject of the equation (v = _______)
v=a times /_\t
300
What two shapes do you need to know the area for when calculating the distance travelled in a speed-time graph?
Rectangle + Triangle
300
2020 Exam (Question 1c) - DOUBLE POINTS
Use the graph to calculate Felix’s acceleration in the first 30 seconds. Show all working
a=(/_\v)/(/_\t)
a=(300 ms^(-1))/(30 s)
a =10ms-2
400
A whale shark swims 390 m in 30 seconds. How fast did it swim. Show all working
v=(/_\d)/(/_\t)
v=(390 m)/(30 s)
v = 13 ms-1
400
How long does it take the object to travel 7 m?
8 s
400
A bee increases its speed by 0.023 ms-1 over 0.44 seconds. How fast does it accelerate? Round your answer to 2.s.f. Show all your working
a=(/_\v)/(/_\t)
a=(0.023 ms^(-1))/(0.44 s)
a = 0.052 ms-2
400
What are the two equations used to calculate the area of the two shapes needed to calculate the distance travelled in a speed-time graph?
Arectangle = base x height
Atriangle = 0.5 x base x height
400
2018 (Question 1a) - DOUBLE POINTS
From the graph, which runner has the greater acceleration in the first 3 seconds?
Explain your answer (calculations are not required).
Runner A has the greater acceleration during the first 3 seconds. The gradient / slope of a speed-time graph equals the acceleration of the object. The steeper the slope, the greater the acceleration. Runner A has a steeper slope than Runner B in the first 3 seconds.
500
A car drives at a speed of 21 ms-1 for 37 seconds. How far did it travel? Round our answer to 3.s.f. Show all working
d=v times/_\t
d=21 ms^(-1) times37 s
v = 777 m
500
Calculate the speed in section B (in your calculations, make sure you show what df, di, tf and ti are). Show all your working
v=(/_\d)/(/_\t)
v=((2200 m - 300 m))/((220 s - 40 s))
v=(1900 m)/(180 s)
v = 10.56 ms-1
500
A waka accelerates at a rate of 2.5 ms-2. This causes the speed of the waka to change from 15 ms-1 to 21 ms-1. How long did it take to change the waka's speed? Show answer to 3.s.f. Show all your working
t=(/_\v)/a
t=(6 ms^(-1))/(2.5 ms^(-2))
t = 3.25 s
500
Calculate the total distance travelled in the first 12 seconds. Show your working
40 m
Teacher to show working on board
500
2019 Exam (Q1d) - DOUBLE POINTS
Show that the total distance travelled by the boat is 1,650 m. Show your working.
Proved that total distance = 1,650 m