Class 11 Physics Model Question Set E

If the percentage errors in measuring the length and breadth of a rectangle are 2% and 3% respectively, the maximum percentage error in its area is:

a. 1%

b. 5%

c. 6%

d. 9%

The scalar product of two perpendicular vectors is:

a. AB

b. –AB

c. Zero

d. A + B

The area under a velocity-time graph represents:

a. Acceleration

b. Displacement

c. Force

d. Momentum

A block is placed on a rough horizontal surface. Which force opposes its tendency to slide?

a. Normal reaction

b. Frictional force

c. Gravitational force

d. Centripetal force

The amount of heat required to change a substance from liquid to vapour at constant temperature is called:

a. Specific heat

b. Latent heat of fusion

c. Latent heat of vaporization

d. Thermal capacity

The electric field inside a conductor in electrostatic equilibrium is:

a. Infinite

b. Maximum

c. Zero

d. Variable

The SI unit of electric potential is:

a. Coulomb

b. Volt

c. Farad

d. Ampere

The capacitance of a parallel plate capacitor increases when:

a. The plate separation increases

b. The plate area decreases

c. The plate area increases

d. The charge is removed

Kirchhoff's junction rule is based on the conservation of:

a. Energy

b. Charge

c. Momentum

d. Mass

The energy released in a nuclear reaction is mainly due to:

a. Change in electrical resistance

b. Mass defect

c. Change in temperature

d. Change in pressure

At absolute zero temperature, a pure semiconductor behaves approximately as:

a. A conductor

b. An insulator

c. A superconductor

d. A perfect resistor

The velocity-time graph of a vehicle is shown below.

(a) Calculate the acceleration during the first 5 seconds.

(b) Calculate the distance covered during the first 15 seconds.

(c) Find the retardation during the last 5 seconds.

A 10 kg wooden block is pulled along a horizontal floor by a horizontal force of 50 N. The coefficient of kinetic friction between the block and the floor is 0.2.

Take .

(a) Draw a labelled free-body diagram of the block.

(b) Calculate the frictional force.

(c) Calculate the acceleration of the block.

(a) What is the banking of roads?

(b) Derive the expression for the safe speed of a vehicle on a frictionless banked road:

(c) Calculate the safe speed if , and .

A hydraulic press has a small piston of cross-sectional area and a large piston of cross-sectional area . A force of 100 N is applied to the small piston.

(a) State Pascal's law.

(b) Calculate the force produced at the large piston.

(c) Mention one practical application of a hydraulic press.

(a) State Boyle's law.

(b) A gas occupies a volume of 600 cm³ at a pressure of . If its temperature remains constant and the pressure is increased to , calculate its new volume.

(c) Why is the process called isothermal?

(a) Define specific latent heat of fusion.

(b) Calculate the heat required to convert 0.25 kg of ice at into water at . Take the specific latent heat of fusion of ice as .

(c) Why does the temperature remain constant during melting?

A string fixed at both ends vibrates in its second harmonic mode, as illustrated below.

(a) Define stationary waves.

(b) If the length of the string is 1.2 m and the wave speed is 120 m/s, calculate its fundamental frequency.

(c) How many antinodes are formed in the second harmonic?

An object is placed 30 cm in front of a concave mirror having a focal length of 15 cm.

(a) Draw a labelled ray diagram for this situation.

(b) Calculate the image distance using the mirror formula.

(c) State the nature of the image.

A light ray passes through a glass prism of refracting angle . At minimum deviation, the angle of deviation is .

(a) Define angle of minimum deviation. [1]

(b) Calculate the refractive index of the prism material. [2]

(c) State one condition for minimum deviation. [1]

A parallel plate capacitor consists of two plates, each having an area of , separated by a distance of in air.

(a) Define capacitance.

(b) Calculate the capacitance of the capacitor.

Take .

(c) What happens to its capacitance if the separation between the plates is doubled?

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

(b) A 1200 kg car moves around a circular track of radius 60 m at a constant speed of 15 m/s.

(i) Calculate its centripetal acceleration.

(ii) Calculate the centripetal force required to maintain its circular motion.[2]

(a) State and explain the first law of thermodynamics.

(b) A metal plate of thickness 0.04 m and area separates two regions maintained at temperatures and . If the thermal conductivity of the material is , calculate the rate of heat flow through the plate.

(c) An ideal gas occupies a volume of at a pressure of and temperature of 300 K. Calculate the number of moles of gas.

Take .

(a) What is dispersion of light? Explain briefly why white light splits into different colours when passing through a glass prism.

(b) Draw a labelled diagram showing the dispersion of white light through a triangular prism.

(c) A prism has a refracting angle of and a refractive index of 1.5. Calculate its angle of minimum deviation using:

(a) A straight conductor of length 0.5 m carries a current of 4 A perpendicular to a uniform magnetic field of 0.2 T.

(i) State the expression for the magnetic force on the conductor.

(ii) Calculate the magnetic force acting on the conductor.

(b) Define mass defect and binding energy of a nucleus.

(c) The mass defect of a nucleus is . Calculate its binding energy in MeV.

Take . [2]