Turning Effect of Forces – Online MCQs Test – Physics 9th

1. According to the second condition for equilibrium:

sum of the all forces acting on a body must be equal to zero

sum of all torques acting on a body is constant

sum of the all, forces acting on a body must be constant

sum of all torques acting on a body is zero

2. A force of 15 N makes an angle of 60 with horizontal. Its vertical component will be:

15N

13N

10N

3. The Center of gravity of uniform square or a rectangular sheet is the:

the point of intersection of its medians

the mid-point on its axis

point of intersection of its diagonals

its center

4. The Center of gravity of a uniform triangular sheet is:

point of intersection of its diagonals

the mid-point on its axis

its center

the point of intersection of its medians

5. Stability of a racing car is increased by:

lowering its centre of gravity

increasing its height

raising its centre of gravity

decreasing its width

6. States of equilibrium are:

three

five

four

two

7. A body is in unstable equilibrium after slight tilt if its center of gravity:

is positioned at its bottom

remains above the point of contact

passes over the point of contact

remains on one side of the point of contact

8. Torque depends upon:

the mass and fulcrum

the magnitude of the velocity and fulcrum

the direction of the force and fulcrum

the magnitude of the force and fulcrum

9. Head to tail rule can be used to add_______ forces.

five

any number of

three

two

10. If a body is slightly titled and does not return back to its previous position, the body is said to be in:

none of these

stable equilibrium

unstable equilibrium

neutral equilibrium

11. States of equilibrium are:

two

four

five

three

12. They form a couple.

two unlike parallel forces of the same magnitude acting along the same line

two Like parallel forces of the same magnitude not acting along the same line

two unlike parallel forces of the same magnitude not acting along the same line

two Like parallel forces of the same magnitude acting along the same line

13. To form a couple, two forces must be:

equal in magnitude

parallel, but opposite in direction

all of these

separated by a distance

14. The forces that act along opposite directions are called:

unlike parallel forces

parallel forces

like parallel forces

none of these

15. Graphical method is used for addition of:

one dimensional vector quantities

two dimensional vector quantities

three dimensional vector quantities

all of these

16. The following expression represents:

the second condition of equilibrium

the first condition of equilibrium

Newton’s second law of motion

Newton’s first Law of motion

17. sin θ =:

perpendicular / hypotenuse

base / hypotenuse

perpendicular / base

base / hypotenuse

18. A right rope walker carries a long pole to:

raise his centre of gravity

keep his centre of gravity in fixed position

increase his weight

lower his centre of gravity

19. According to the first condition for equilibrium:

sum of all torques acting on a body is constant

sum of the all forces acting on a body must be equal to zero

sum of the all forces acting on a body must be constant

sum of all torques acting on a body is zero

20. Force has:

both magnitude and direction

only magnitude

only direction

none of these

Class 9th | Physics | Chapter 4 | Turning Effect of Forces | Online MCQs Test