Class 11 Physics Model Question Set A

The dimensional formula of gravitational constant is:

a.
b.
c.
d.

A body moves with initial velocity and uniform acceleration . Its velocity after 4 seconds will be:

a.
b.
c.
d.

The moment of inertia of a uniform circular disc about an axis passing through its centre and perpendicular to its plane is:

a.
b.
c.
d.

A body is projected vertically upward. At its highest point, which of the following quantities becomes zero?

a. Acceleration

b. Gravitational force

c. Velocity

d. Potential energy

The specific heat capacity of a substance is . The heat required to raise the temperature of 2 kg of the substance by 10 K is:

a. 5000 J
b. 10000 J
c. 15000 J
d. 20000 J

Two waves of equal frequency travelling in the same direction produce a resultant wave. When their phase difference is 180 ∘ 180 ∘ , the interference is:

a. Constructive

b. Destructive

c. Stationary

d. Progressive

The electric field intensity at a distance from a point charge in vacuum is:

a.
b.
c.
d.

Two resistors of 4 Ω and 6 Ω are connected in parallel. Their equivalent resistance is: [1]

a. 10 Ω

b. 5 Ω

c. 2.4 Ω

d. 24 Ω

The magnetic force on a charged particle moving parallel to a uniform magnetic field is: [1]

a. Maximum

b. Minimum but non-zero

c. Zero

d. Infinite

The energy of a photon of frequency is approximately: [1]

(Given: )

a.
b.
c.
d.

The half-life of a radioactive substance is 4 days. What fraction of the original substance remains after 12 days?

a.
b.
c.
d.

a. Define projectile motion.

b. Derive an expression for the horizontal range of a projectile projected with velocity at an angle with the horizontal.

c. A ball is projected from the ground with a velocity of at an angle of with the horizontal. Calculate its maximum height and horizontal range.

(Given: )

a. What is meant by the centre of mass of a system?

b. State and explain the principle of conservation of linear momentum.

c. A bullet of mass 20 g is fired horizontally from a gun of mass 4 kg with a velocity of . Calculate the recoil velocity of the gun.

a. Define the coefficient of linear expansion.

b. Draw a labelled diagram of a bimetallic strip and explain its working when heated.

c. A steel rod of length 2 m is heated from to . Calculate the increase in its length.

(Given: coefficient of linear expansion of steel ).

a. What is meant by the fundamental frequency of a stretched string?

b. Establish the relationship between the velocity, frequency and wavelength of a progressive wave.

c. A stretched string of length 1.2 m vibrates in its fundamental mode. If the wave velocity is , calculate its fundamental frequency. Draw the corresponding vibration pattern.

a. State Coulomb's law of electrostatic force.

b. Draw the electric field pattern around two equal positive point charges.

c. Two point charges of and are separated by a distance of 0.3 m in vacuum. Calculate the electrostatic force between them.

(Given: ). [2]

a. Define drift velocity of free electrons.

b. Draw a circuit diagram showing two resistors connected in series with a battery and a key.

c. A battery of emf 12 V and internal resistance 1 Ω is connected to an external resistance of 5 Ω. Calculate the current in the circuit and terminal potential difference of the battery.

a) State Gauss's law in electrostatics.

b) Derive a relation between electric field intensity and potential gradient.

c) A charged particle of mass 1.0 g is suspended through a silk thread of length 40 cm in a horizontal uniform electric field of , as shown in the figure. If the particle stays at a distance of 24 cm from the vertical in equilibrium, find the charge on the particle.

a. What is electromagnetic induction?

b. State Faraday's law of electromagnetic induction.

c. A coil having 200 turns experiences a change in magnetic flux from to in 0.02 seconds. Calculate the magnitude of induced emf.

a. What is meant by mass defect of a nucleus?

b. Explain the difference between nuclear fission and nuclear fusion with one example of each.

c. The mass defect of a helium nucleus is 0.0304 u. Calculate its total binding energy.

(Given: ). [2]

a) Define drift velocity. Derive the relationship between the drift velocity of free electrons and electric current in a metallic conductor.

b) Two electric bulbs rated 60 W, 220 V and 40 W, 220 V are connected in series across a 220 V supply, as shown in the figure. Calculate the actual power consumed by each bulb.

Newton's Laws of Motion

a. State Newton's second law of motion and derive the relation .

b. A block of mass 5 kg is placed on a rough horizontal surface. A horizontal force of 30 N acts on it. If the coefficient of friction between the block and the surface is 0.2, calculate:

i. Frictional force
ii. Acceleration of the block

c. Draw a free-body diagram of the block showing all the forces acting on it.

(Given: )

a. Define electric potential at a point. Write its SI unit.

b. Derive the expression for the capacitance of a parallel-plate capacitor.

c. Two capacitors of capacitances and are connected in series across a 100 V battery. Calculate:

1. Equivalent capacitance.

2. Charge stored in each capacitor.

3. Potential difference across each capacitor.

a. Why is water considered more elastic than air? Give a suitable explanation.

b. What is elastic potential energy? Derive an expression for the energy stored in a stretched wire.

c. A wire of length 2.0 m and cross-sectional area supports a load of 12 kg. Calculate the extension produced in the wire and the elastic potential energy stored in it. The Young's modulus of the wire is .

a. What is the photoelectric effect? Define the threshold frequency of a metal.

b. State Einstein's photoelectric equation and explain the laws of the photoelectric effect.

c. Light of wavelength is incident on a metal surface having a work function of . Calculate:

1. Energy of the incident photon.

2. Maximum kinetic energy of the emitted photoelectrons.

3. Stopping potential.

Given: