[Class 11th - Physics - System of Particles and Rotational Motion - MERIT YARD]

[Class 11 - Rotational Motion]

Question 1 / 40A rigid body is a body in which:

A) Shape changes easily

B) Distance between any two particles remains constant

C) Volume is zero

D) Mass is zero

Question 2 / 40The turning effect of force is called:

A) Momentum

B) Torque

C) Work

D) Power

Question 3 / 40Formula for Torque (τ) is:

A) Force × Time

B) Force / Area

C) Force × Perpendicular Distance (r × F)

D) Mass × Velocity

Question 4 / 40The rotational analogue of Mass is:

A) Torque

B) Moment of Inertia

C) Angular Momentum

D) Angular Velocity

Question 5 / 40SI Unit of Torque is:

A) Newton

B) Joule / Second

C) Newton-meter (Nm)

D) Kg m/s

Question 6 / 40Centre of Mass of a uniform ring lies:

A) On the circumference

B) Inside the material

C) At the geometric center

D) Nowhere

Question 7 / 40Angular Momentum (L) is defined as:

A) mvr

B) r × p

C) Iω

D) All of the above

Question 8 / 40Relation between Linear Velocity (v) and Angular Velocity (ω) is:

A) v = rω

B) v = ω/r

C) ω = rv

D) v = r²ω

Question 9 / 40Moment of Inertia depends on:

A) Mass only

B) Size and Shape only

C) Distribution of mass around axis

D) All of these

Question 10 / 40Moment of Inertia of a thin Ring about an axis through its center is:

A) ½ MR²

B) MR²

C) 2/5 MR²

D) MR²/4

Question 11 / 40Moment of Inertia of a Circular Disc about its center is:

A) ½ MR²

B) MR²

C) 2/3 MR²

D) MR²/12

Question 12 / 40If external Torque is zero, what is conserved?

A) Linear Momentum

B) Kinetic Energy

C) Angular Momentum

D) Potential Energy

Question 13 / 40The product of Force and Lever Arm is:

A) Power

B) Torque (Moment of Force)

C) Impulse

D) Work

Question 14 / 40A couple consists of:

A) Two equal and opposite forces along different lines of action

A) Two equal and opposite forces along different lines

B) Two unequal forces

C) Two forces in same direction

D) Single force

Question 15 / 40Radius of Gyration (k) is defined by relation:

A) I = M/k

B) I = Mk²

C) k = MI

D) I = M²k

Question 16 / 40Newton's Second Law for Rotation is:

A) F = ma

B) τ = Iα

C) τ = dL/dt

D) Both B and C

Question 17 / 40Work done by a Torque is:

A) τ × θ

A) τ × θ (Torque × Angle)

B) τ × t

C) F × d

D) I × α

Question 18 / 40Power in Rotational Motion is:

A) P = Fv

B) P = τω

C) P = Iα

D) P = Work / Angle

Question 19 / 40Rotational Kinetic Energy is:

A) ½ mv²

B) ½ Iω²

C) Iω

D) mgh

Question 20 / 40The motion of Center of Mass is affected by:

A) Internal Forces

B) External Forces

C) Shape of body

D) None

Question 21 / 40Condition for translational equilibrium is:

A) Net Force = 0

B) Net Torque = 0

C) Velocity = 0

D) Acceleration = 0

Question 22 / 40Condition for rotational equilibrium is:

A) Net Force = 0

B) Net Torque = 0

C) Angular Velocity = 0

D) Momentum = 0

Question 23 / 40Relation between Linear Acceleration (a) and Angular Acceleration (α) is:

A) a = α/r

B) a = rα

C) α = ar

D) a = r²α

Question 24 / 40If a person sitting on a rotating chair stretches his arms, his speed:

A) Increases

B) Decreases

C) Remains same

D) Becomes zero

Question 25 / 40Cross product of two parallel vectors is:

A) Zero

B) 1

C) Maximum

D) Negative

Question 26 / 40Moment of Inertia of a Solid Sphere about diameter is:

A) 2/3 MR²

B) 2/5 MR²

C) MR²

D) ½ MR²

Question 27 / 40In pure rolling motion, velocity of the point of contact with ground is:

A) v

B) Zero

C) 2v

D) -v

Question 28 / 40Which physical quantity is represented by the area under Torque-Angle graph?

A) Power

B) Work Done

C) Impulse

D) Force

Question 29 / 40Vector product obeys commutative law (A×B = B×A)?

A) Yes

B) No (A×B = - B×A)

C) Sometimes

D) Only for unit vectors

Question 30 / 40Direction of Angular Velocity vector is along:

A) The radius

B) The axis of rotation

C) The tangent

D) Perpendicular to axis

Question 31 / 40A flywheel is used in engines to:

A) Increase speed

B) Maintain uniform motion (store energy)

C) Decrease friction

D) Look heavy

Question 32 / 40Force F=10N acts at distance r=2m. If angle is 90°, Torque is:

A) 5 Nm

B) 20 Nm

C) 12 Nm

D) 8 Nm

Question 33 / 40Total Kinetic Energy of a rolling body is sum of:

A) Translational KE + Potential Energy

B) Translational KE + Rotational KE

C) Rotational KE only

D) Translational KE only

Question 34 / 40Unit of Moment of Inertia is:

A) kg m

B) kg m²

C) kg/m²

D) N m

Question 35 / 40A wheel rotates at 300 rpm. Its angular velocity in rad/s is:

A) 30π

B) 10π

C) 300π

D) 5π

Question 36 / 40The centre of mass of two particles lies on the line joining them:

A) Closer to lighter mass

B) Closer to heavier mass

C) Exactly at center

D) Anywhere

Question 37 / 40Door handles are placed at the edge to:

A) Increase force required

B) Increase torque with less force

C) Decrease torque

D) For design

Question 38 / 40Mass=2kg, Radius=1m. Moment of Inertia of Ring is:

A) 1 kg m²

B) 2 kg m²

C) 4 kg m²

D) 0.5 kg m²

Question 39 / 40Dimensional formula of Torque is same as:

A) Force

B) Work / Energy

C) Power

D) Momentum

Question 40 / 40Two bodies of mass 2 kg and 4 kg are at x=0 and x=6m. Where is the Center of Mass?

A) 2 m

B) 4 m

C) 3 m

D) 5 m

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