Sub. code 1
NEB — GRADE XI
Model Question
Physics Question Paper (Model Question)
The candidates are required to give their answers in their own words as far as practicable. The figures in the margin indicate full marks.
Pass Marks : 32
सबै प्रश्नको उत्तर दिनुहोस् । (Attempt All Questions)
This model question question paper is for Class 11 Physics, (subject code 1), carrying full marks of 75 with a pass mark of 32, to be completed within 3hrs. Answers with step-by-step solutions are available for every question below.
Group A
Rewrite the correct options in your answer sheet
A metre rule is used to measure the length of a piece of string in a certain experiment. It is found to be $20 \text{ cm}$ long to the nearest millimeter. How should this result be recorded in a table of results?
$0.2000 \text{ m}$
$0.200 \text{ m}$
$0.20 \text{ m}$
$0.2 \text{ m}$
Forces are applied to a rigid body. The forces all act in the same plane. In which diagram is the body in equilibrium?
An athlete makes a long jump and follows a projectile motion. Air resistance is negligible.
Which one of the following statements is true about the athlete?
The athlete has constant horizontal and vertical velocities.
The athlete has constant horizontal velocity and constant downward acceleration.
The athlete has constant upward acceleration followed by a constant downward acceleration.
The athlete has a constant upward velocity followed by a constant downward velocity.
At Kulekhani-I Hydro-power station, water flows from Indra Sarowar into the turbines that are a vertical distance of $550 \text{ m}$ below the lake, as shown in the diagram. Generally, $780,000 \text{ kg}$ of water flows into the turbines every minute. The turbines have the efficiency of $85%$. What is the output power of the turbines?
$71 \text{ MW}$
$60 \text{ MW}$
$4.2 \text{ GW}$
$3.6 \text{ GW}$
Graphs of stress-strain for four different materials are shown below. Which graph represents the stiffest material?
A boy walks towards a stationary plane mirror at a speed of $1.2 \text{ m s}^{-1}$. What is the relative speed of approach of the boy and his image?
$0$
$1.2 \text{ m s}^{-1}$
$2.4 \text{ m s}^{-1}$
$1.44 \text{ m s}^{-1}$
The critical angle between an equilateral prism and air is $45^\circ$. What happens to the incident ray perpendicular to the refracting surface?
It is reflected totally from the second surface and emerges perpendicular from the third surface.
It gets reflected from second and third surfaces and emerges from the first surface.
It keeps reflecting from all the three sides of the prism and never emerges out.
After deviation, it gets refracted from the second surface.
In the formation of a rainbow, the light from the sun on water droplets undergoes which of the following phenomenon/phenomena?
dispersion only
only total reflection
dispersion and total internal reflection
scattering
In what unit is the power of lens measured?
watt
metre
dioptre
Hertz
A piece of wire of resistance $R$ is bent through $180^\circ$ at mid-point and the two halves are twisted together. What is the resistance of the wire thus formed?
$R/4$
$R/2$
$R$
$2R$
What are the elementary particles with half spin called?
quarks
bosons
fermions
hadrons
Group B
Answer the following question
State the law of conservation of momentum.
A jumbo jet of mass travelling at a speed of lands on the airport. It takes to come to rest. Calculate the average force applied by the ground on the aeroplane.
After landing the aeroplane’s momentum becomes zero. Explain how the law of conservation holds here.
State Hooke’s law.
The walls of the tyres on a car are made of a rubber compound. The variation with stress of the strain of a specimen of this rubber compound is shown in Fig. As the car moves, the walls of the tyres bend and straighten continuously. Use Fig. to explain why the walls of the tyres become warm.
What is meant by specific latent heat of vaporization of water = $2.26 \text{ MJ kg}^{-1}$?
A $1.0 \text{ kW}$ kettle contains $500 \text{ g}$ of boiling water. Calculate the time needed to evaporate all the water in the kettle. (Specific latent heat of vaporization of water = $2.26 \text{ MJ kg}^{-1}$).
Explain why the actual time needed is a little longer than the time calculated in 2(b).
State any three properties of an ideal gas as assumed by the kinetic theory of gas.
A student needed to use the ideal gas for a certain experiment. But, the ideal gas does not exist. Suggest what two different things this student could do to solve his problem.
Define temperature gradient in an object.
An electric kitchen range has a total wall area of $1.40 \text{ m}^2$ and is insulated with a layer of fiber glass that has a temperature of $175^\circ \text{C}$ and its outside surface is $35^\circ \text{C}$. The fiber glass has a thermal conductivity of $0.040 \text{ W m}^{-1} \text{K}^{-1}$. Calculate the rate of flow of heat through the insulation, assuming the fibre as a flat slab of area $1.40 \text{ m}^2$.
How might the rate of conduction be affected if the fiber absorbs moisture? Justify your answer.
Paper Overview & Analysis
Year
Model Question
Type
75
Full Marks
32
Pass Marks
3hrs
Duration
24
Question Items
Question Type Breakdown
Group Breakdown