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

1. A pair of unlike parallel forces having different lines of force produce _________:

equilibrium

unstable equilibrium

torque

a couple

2. According to the second condition for equilibrium:

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

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 all torques acting on a body is zero

3. The following expression represents:

the second condition of equilibrium

Newton’s first Law of motion

the first condition of equilibrium

Newton’s second law of motion

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

the mid-point on its axis

point of intersection of its diagonals

the point of intersection of its medians

its center

5. When a body is slightly displaced and then released it returns to its previous position then the equilibrium will be:

stable equilibrium

None of these

unstable equilibrium

neutral equilibrium

6. They form a couple.

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

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

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

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

the point of intersection of its medians

point of intersection of its diagonals

the mid-point on its axis

its center

8. A body is in stable equilibrium after slight tilt if its center of gravity:

remains above the point of contact

is at Lowest position

remains on one side of point of contact

passes over the point of contact

9. perpendicular / base = :

cosec θ

sin θ

tan θ

cos θ

10. S.I unit of the torque or moment of force is:

Newton per second

Newton second

Newton

Newton metre

11. Graphical method is used for addition of:

one dimensional vector quantities

two dimensional vector quantities

three dimensional vector quantities

all of these

12. States of equilibrium are:

two

five

three

four

13. Torque depends upon:

the mass and fulcrum

the magnitude of the velocity and fulcrum

the magnitude of the force and fulcrum

the direction of the force and fulcrum

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

equal in magnitude

separated by a distance

parallel, but opposite in direction

all of these

15. The turning effect of force is called:

moment of force

none of these

moment of force and torque

torque

16. A body must satisfy __________ conditions to be in equilibrium.

five

two

four

three

17. A wall hanging, buildings, bridges or any object lying in rest on the ground are some examples of:

inertia

dynamic equilibrium

acceleration due to gravity

static equilibrium

18. sin θ =:

base / hypotenuse

perpendicular / hypotenuse

perpendicular / base

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

increase his weight

raise his centre of gravity

keep his centre of gravity in fixed position

lower his centre of gravity

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

three

five

two

any number of

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