Speed is the scalar quantity listed and acceleration is measured in m/s², so this Class 9 sheet opens by sorting scalars from vectors and fixing the acceleration unit. Uniform motion means constant speed and constant direction, with s = ut + ½at² in the answers.
Key Takeaways
Speed is a scalar quantity (Q1).
The SI unit of acceleration is m/s² (Q2).
Q6 records s = ut + ½at².
Section A: Multiple Choice Questions (1 Mark Each)
(a) constant speed and constant direction(b) changing speed but constant direction(c) constant speed but changing direction(d) changing speed and direction
4.On a distance-time graph, the slope of the graph gives the
(a) displacement of the body(b) acceleration of the body(c) speed of the body(d) force on the body
5.The area under a velocity-time graph represents the
(a) acceleration of the body(b) displacement of the body(c) retardation of the body(d) speed of the body
6.For a body moving with uniform acceleration, the distance travelled in time t is given by
(a) s = ut + ½at²(b) s = ut - ½at²(c) s = ut + at(d) s = ut - at
Section B: Short Answer Type Questions (2 Marks Each)
Show all steps clearly.
7.Define speed. State its SI unit.
8.Distinguish between distance and displacement.
9.What is uniform circular motion? Give one example.
10.When is a body said to be in uniform acceleration?
11.State the first equation of motion and name the symbols used.
12.What does the slope of a velocity-time graph represent?
13.A body is thrown vertically upward. What is the acceleration acting on it at the highest point?
14.What is the difference between average speed and instantaneous speed?
Section C: Numericals & Word Problems (3 Marks Each)
Apply the concepts to solve the problems. Show all working.
15.A car travels 200 km in 4 hours. Find its average speed in km/h and in m/s. (Average speed = total distance ÷ total time)
16.A body starts from rest and moves with a uniform acceleration of 2 m/s². Find the distance travelled by it in 5 seconds. (Use s = ut + ½at²)
17.A train moving at 20 m/s is brought to rest by applying brakes in 10 seconds. Find the retardation and the distance travelled before it stops. (Use v = u + at and s = ut + ½at²)
18.A ball is thrown vertically upward with a velocity of 20 m/s. Find the maximum height reached. (g = 10 m/s², use v² = u² - 2gh)
19.A car increases its speed uniformly from 5 m/s to 25 m/s in 4 seconds. Find the acceleration of the car. (a = (v - u) ÷ t)
20.A bus starts from rest and moves with uniform acceleration, covering 240 m in 20 seconds. Find the acceleration of the bus. (Use s = ut + ½at²)
Answer Key
1. c) Speed
2. b) m/s²
3. a) constant speed and constant direction
4. c) speed of the body
5. b) displacement of the body
6. a) s = ut + ½at²
7. Refer to solution guide.
8. Refer to solution guide.
9. Refer to solution guide.
10. Refer to solution guide.
11. Refer to solution guide.
12. Refer to solution guide.
13. Refer to solution guide.
14. Refer to solution guide.
15. Refer to solution guide.
16. Refer to solution guide.
17. Refer to solution guide.
18. Refer to solution guide.
19. Refer to solution guide.
20. Refer to solution guide.
End of Worksheet
People Also Ask
Which of these is a scalar quantity?
Speed, option (c) in this worksheet (Q1).
What is the SI unit of acceleration?
m/s², option (b) in this worksheet (Q2).
What is the second equation of motion?
s = ut + ½at², option (a) in this worksheet (Q6).
Stuck on a similar problem? Clear your next doubt instantly with the Doubt Solver.
Browse more free worksheets for CBSE Grade 9.