Physics MCQs for Class 9 with Answers Chapter 3

If Fx and Fy are rectangular components of vector F, then its direction is determined by the relation

θ = sin-1 Fv/Fx

θ = tan-1 Fx/Fy

θ = tan Fx/Fy

θ = tan Fy/Fx

The value of sin θ at an angle of 60o is

0.5

0

0.707

0.866

The right angle triangle length of bas is 4 cm and its hypotenuse is 5 cm, then length of perpendicular is:

1 cm

3 cm

9 cm

20 cm

The number of forces that can be added by head to tail rule are

2

3

4

Any Number

The unit of torque is:

N

Nm

m

m/n

After tilting if body come back to its original position then the body is in:

Stable equilibrium

unstable equilibrium

Neutral equilibrium

Equilibrium

Turning effect of a force is called:

Torque

Moment

Couple

Torque and momentum

The value of tan 45ois:

0.5

1.732

1

0.5777

__________ forces have opposite direction:

Unlike parallel

Parallel

Like parallel

None of these

In a right angle triangle base is 4 cm and perpendicular is 3 cm length of diagonal will be:

2 cm

5 cm

4 cm

6 cm