Grade 11 Physics 2071 Pastpaper
Physics
Grade 11 , 2071
Regular Examination Paper
Pass Marks : 35
Time : 03:00:00
What do you mean by the banking of a curved path? Derive an expression for the banking angle.
Does cubical expansively depend upon the initial volume of a solid? Write the unit of this expansivity. Also derive its relation with superficial expansivity.
What is the physical difference between electric potential are electric field intensity? Derive an expression for the potential differences between two points in the electrostatic field.
The element of an electric fire with an output of 1.5 Kw is a cylinder of 0.3 m Iong and 0.04 m in radius. Calculate its temperature if it behaves as a black body.
How does the frequency of vibration of a simple pendulum related with its length? Hence estimate the frequency of a second's pendulum.
A force (in Newton) expressed in vector notation as F =( 2 î + ĵ - 3 K̂ ) is applied on a body so that the displacement produced in meter is given by D = ( i ̂ - 2 j ̂ - 3 k̂). Express the result and nature of the work done.
Express the dimension of the velocity gradient from the definition of the coefficient of viscosity.
In usual notation, a simple harmonic motion is given as y = a sin (wt - θ ). Find acceleration.
What is a black hole? Write down its characteristic features.
Explain the significance of the banking of a curved road.
What is the difference between a real and an ideal gas? Explain on the basis of the hypothesis of the kinetic theory.
Explain the significance of anomalous expansion of water with an example observed in nature.
Entropy is defined in the second law of thermodynamics. Can the first law be expressed in terms of entropy? How?
Spherical mirror may behave as a plane mirror as a special case. Explain.
Two positive charges separated by a distance create an electrostatic field Can i. electric potential, and {ii) electric field intensity be zero at a point between the charges? Justify your answer
Three capacitorsof the same capacitance are joined in (i) series, and (ii) all in parallel.By how much one of these combinations is larger in magnitude? Explain.
Define torque and couple in rotational motion. Derive an expression for the work done by the couple.
What do you understand by Poisson's ratio? Derive an expression for energy stored in a stretched wire.
Explain the concept of geostationary satellite. Find an expression for the total energy of the moon revolving around the earth
What is elastic collision? Prove that the colliding objects exchange their velocities in one dimensional elastic collision.
Define the coefficient of thermal conductivity, Describe, with necessary theory, an experiment for its determination in the laboratory.
How will you make difference between real and virtual images? Obtain an expression for the relation between object distance, image distance and the focal length in the case of a convex mirror.
State and explain Gauss law. Use it to find the electric field due to a charged conducting sphere (i) outside, and (ii) inside.
Define capacitance of a capacitor. Deduce an expression for the capacitance of a parallel plate capacitor.
A 650 KW power engine of a vehicle of mass 1.5 x 105 Kg is rising on an inclined plane of inclination 1 in 100 with a constant speed of 60 km/hr. Find the frictional force between the wheels of the vehicle and the plane.
A mass of 0.2 Kg is rotated by a string at a constant speed in a vertical circle of radius 1 m. If the minimum tension in the string is 3 N, calculate the magnitude of the speed and the maximum tension in the string.
Find the work done required breaking up a drop of water of radius 5 x 10-3 m into eight drops of water, assuming isothermal condition.
A bullet is fired with a velocity of 100 m/s from the ground at an angle of 60° with the horizontal. Calculate the horizontal range covered by the bullet. Also calculate the maximum height attained.
Air is compressed adiabatically to half of its volume. Calculate the change in its temperature.
A Carnot engine works between the source and the sink with efficiency 40%. How much temperature of the sink be lowered keeping the source temperature constant so that its efficiency increases by 10%?
What is the apparent position of an object below a rectangular glass slab of refractive index 1.45 and the thickness 0.06 m if a layer of water 0.05 m thick is on the top of the glass slab?
Explain the difference between a "push" and a "pull" in the case of a heavy roller on a level road where the force acts on the roller making an angle with the horizontal road.
A bomb is to be dropped from a moving helicopter on a target on the ground. Explain how it can hit the target.
A force (in Newton) expressed in vector notation as F = 4i + 7 ĵ - 3 k̂ is applied on a body and produces a displacement (in meter), D = 3î - 2ĵ - 5K̂ in 4 seconds. Estimate the power.
A student writes an expression of the force causing a body of mass (m) to move in a circular motion with a velocity (v) as F = mv2. Use the dimensional method to check its correctness.
Explain the difference between a simple and conical pendulum.
A SHM is represented as y =a cos (wt+ ϕ) in usual notation. Find its acceleration.
What is a black hole? Write down its characteristic features.
Why are dews formed in the clear nights but not in the cloudy ones? Explain.
Define the coefficient of cubical expansion of a solid and hence write an expression for the variation of its density with temperature.
Explain the significant difference between the first and the second laws of thermodynamic.
Draw an outline sketch to show the chromatic aberration in the case of a lens. How can achromatism be achieved?
What do you understand by 1 lumen and 1 phot? What do they signify?
Explain the difference between a polar end a non-polar dielectrics with one example of each.
How can a neutral body be charged with negative electricity by induction? Explain.
Define Young's modulus, bulk modulus, modulus of rigidity and Poisson's ratio.
Describe the experimental method to find the coefficient of viscosity of a liquid by Stoke's method.
What do you mean by a rigid body? Obtain an expression for the moment of inertia of a thin and uniform rod about an axis passing through the centre and perpendicular to its length.
Describe in brief the method of mixture to determine the specific heat of a solid in the laboratory?
Derive the ideal gas equation on the basis of theory of kinetic theory of gases.
What is perfect gas? Prove that the average kinetic energy of a gas molecule is directly proportional to the absolute temperature of the gas.
What is an adiabatic process? Prove the relation Pvγ= constant, where notations carry usual meanings.
Sketch an outline diagram of an astronomical telescope and derive expression for its angular magnification when the final image is formed at the least distant of distinct vision.
State and explain Gauss law of electrostatics and apply it to find electric field intensity on the surface and inside the surface of a charged sphere.
A capillary tube of 0.3 m diameter is placed vertically inside a liquid of density 800 Kg -3, surface tension 5 x 10 -4 Nm-1 and angle of contact 30°. Calculate the height to which the liquid rises in the capillary tube.
A stationary mass explodes into two parts of mass 4 kg and 40 kg. The initial kinetic energy of larger mass is 10 J. Find the velocity of the smaller mass.
At what angle should a circular road be banked so that a car running at 50 Km/hr be safe to go round the circular turn of 200 m radius?
An earth satellite moves in a circular orbit with a speed of 6.2 kms-1. Find the time of one revolution and its centripetal acceleration.
A Carnot engine works between "the source and the sink with 25% efficiency. How much temperature of the source be raised keeping the sink at the same constant temperature at 27°C so that the efficiency is increased by 15 %?
From what height should a block of ice be dropped in order that it may melt completely?
At what position an object is placed in front of a concave mirror of radius of curvature 0.4 m so that an erect image of magnification 3 is produced?
Two spheres of radii 5 cm and 10 cm are given charges 100C and 50 C respectively and wire. Calculate the loss of energy after connection.
Three capacitors of 1μ f, 2μf and 3μf .The same capacitors are again connect in parallel. Compare their equivalent capacitance. Which one of these combinations gives larger value of capacitance?