This post contains 9th Class Physics Notes of 4th Chapter. In this post you will find 9th Class physics Chapter 4 MCQs for students. Name of the 4th Chapter in the Physics of class 9 is “Turning Effect of Forces”. These Multiple Choice Questions are available here for Students to practice for exams.
Turning effect of Forces: 9th Class Physics Chapter 4 MCQs for Students
You may also like: MCQs of Chapter 3 – MCQs of Chapter 5
1. The number of perpendicular components of a force is:
(a) 1
(b) 3
(c) 4
(d) 2
2. A force of 10N is making an angle of 30° with horizontal. Its horizontal component will be:
(a) 4N
(b) 5N
(c) 7N
(d) 8.7N
3. Turning effect of a force is called:
(a) Torque
(b) Moment
(c) Couple
(d) Torque and momentum
4. If Fy = 4N and Fx = 3N, what is magnitude of resultant force:
(a) 7N
(b) 5N
(c) 12N
(d) 10N
5. First condition of equilibrium is:
(a) ΣF = 0
(b) Στ = 0
(c) ΣF = 0, Στ = 0
(d) All of These
6. Center of gravity of sphere is at:
(a) Centre of sphere
(b) Outside of sphere
(c) Radius of sphere
(d) none of these
7. The number of forces that can be added by head to tail rule are:
(a) 2
(b) 3
(c) 4
(d) Any number
8. A body is in equilibrium when its:
(a) Acceleration is uniform
(b) Speed and acceleration are uniform
(c) Speed is uniform
(d) Acceleration is non-uniform
9. Formula for the direction of resultant force with the help of rectangular components.
(a) 𝛳 = tan-¹ fx/fy
(b) 𝛳 = tan-¹ fy/fx
(c) 𝛳 = sin-¹ fy/fx
(d) 𝛳 = cos-¹ fy/fx
10. A force of 10N makes an angle of 90° with x-axis. Its horizontal component will be:
(a) 10N
(b) 5N
(c) Zero
(d) Maximum
11. The Conditions of equilibrium are:
(a) 1
(b) 2
(c) 3
(d) 4
12. The states of equilibrium are:
(a) 1
(b) 2
(c) 3
(d) 4
13. Complete equation Fᵧ/Fₓ = _________.
(a) sin 𝛳
(b) cos 𝛳
(c) tan 𝛳
(d) cosec 𝛳
14. Racing cars are made stable by:
(a) Increasing their speed
(b) Decreasing their speed
(c) Decreasing their width
(d) Lowering their centre of gravity
15. The direction of resultant vector can be found by:
(a) 𝛳 = tan fx/fy
(b) 𝛳 = tan fy/fx
(c) 𝛳 = tan-¹ fx/fy
(d) 𝛳 = tan-¹ fy/fx
16. The value of gravitational acceleration “g” on the surface of moon is:
(a) 1.62 ms-²
(b) 3.7 ms-²
(c) 9.8 ms-²
(d) 10 ms-²
17. The value of “g” at a hight one Earth’s radius above the surface of the Earth is:
(a) 2 g
(b) 1/2 g
(c) 1/3 g
(d) 1/4 g
9th Class Physics Chapter 4 Short Questions and Answers are also available.