Important questions of physics of class 11 in MP board for Final exam.
Answers
Answer:
A person walks 8m West and 6m North so the displacement is __________
If the magnitude of two vectors are 3 units and 4 unit and resultant of scalar product is 6 units, then the angle between them is____________
State the triangle law of vector addition and explain it.
What are the fundamental quantities? Name the unit of fundamental quantities. In S.I. System and write their symbol.
The error in measurement of one side of a solid cube is 5%. What will be the percentage error in the measurement of its volume.
Explain one dimensional, two dimensional and three dimensional motion with examples.
Draw position time graph for uniform accelerated motion.
A second hand of a clock is 2 cm long. Calculate (i) Angular velocity (ii) Linear velocity of its tip.
Write Newton’s first law of motion. How is law of inertia, explained by it?
Write the advantages and disadvantage of friction in daily life?
Write down the principle of Rocket propulsion. Obtain expression for upthrust force on a Rocket?
State the theorem of parallel axis of moment of inertia.
State law of conservation of angular momentum. Explain this with an example?
Derive an expression for Kinetic energy and Momentum of a body.
Deduce expression for the elastic potential energy of a compressed spring.
Write down four differences between energy and power.
Explain the condition of weightlessness in artificial satellite and describe the effect of weightlessness with reason?
Write down the different between Isothermal elasticity and adiabatic elasticity.
What is Pascal’s law? How does gravity effect on this law?
Explain Detergentes froth in not water has greater cleansing power.
The effective length of a simple pendulum measures up to the centre of bob: why?
What is Doppler’s effect?
What are the similarities and dissimilarities in the properties of heat radiation and light?
State Stefan- Boltzmann’s Law of black body radiation.
What changes occur in the wavelength and the energy corresponding to it in the radiation emitted from a black body on increasing its temperature? Draw energy distribution cures at two different temperatures to explain it.
Answer:
Q. 1.Name the subjective property of sound related to its frequency and of light related to its wavelength.
Q. 2 (a). (i) A machine raises a load of 750 N through a height of 16 m in 5 seconds. Calculate the power at which the machine works.
(ii) State the principle of conservation of energy.
(b). (i) A cook uses a 'fire tong' of length 28 cm to lift a piece of burning coal of mass 250 g. If he applies his effort at a distance of 7 cm from the fulcrum, what is the effort in S.I. unit? Take g = 10 m/s2.
(ii) State the S.I. unit of the momentum of a body.
(c). (i)The work done by the heart is 1 Joule per beat. Calculate the power of the heart if it beats 72 times in one minute.
(ii) Mention two properties of a wave: one property which varies and the other which remains constant when the wave passes from one medium to another.
Q. 3 (a) Define: (i) Work (ii) Power and (iii) Energy.
(b) How is work done related to the applied force?
(c) By what factor does the kinetic energy of a moving body change when its speed is reduced to half?
(d) What do the following units measure?
Pascal
Kilowatt hour.
(e) From the ground floor, a man comes up to the fourth floor of a building using the staircase. Another person comes up to the same floor using an elevator. Neglecting friction, compare the work done in the two cases.
Q 4.State two ways by which the frequency of transverse vibrations of a stretched string can be decreased.
Q. 5. (i) Define specific heat capacity of a substance. State its S.I. unit.
(ii) Give one example each where high specific heat capacity of water is used:
In cooling
As heat reservoir.
(b) A vessel of negligible heat capacity contains 40 g of ice in it at 0°C. 8 g of steam at 100°C is passed into the ice to melt it. Find the final temperature of the contents of the vessel.
(Specific latent heat of vaporization of steam, = 2268 J/g; Specific latent heat of fusion of ice = 336 J/g and Specific heat capacity of water = 4.2 J/g°C)
Draw a ray diagram to illustrate the action of a convergent lens as a reading lens or a magnifying glass.
A prism deviates a monochromatic ray of light through an angle 'δ' when the angle of incidence at the surface of the prism is 'i'.
Draw a graph showing the variation of 'δ' with 'i'. On Your graph show the angle of minimum deviation.
What is the relation between the angle of incidence and the angle of emergence when the ray suffers minimum deviation.
Q. 6. (i) Draw a neat labelled diagram of an ac generator.
(ii) What is the magnitude of emf induced in the coil when its plane becomes parallel to the magnetic field.
(iii) State two ways by which the emf in an ac generator can be increased.
Q 7. (a) Draw a representative diagram of a dc motor . Label the following in your diagram
(i) the field magnet
(ii) the armature
(iii) commutator and
(iv) brushes. What is the energy changes involved in this case?
Q 8.
If the power of a motor is 40 kW, at what speed can it raise a load of 20,000 N?
A ray of light, after refraction through a concave lens emerges parallel to the principal axis. Draw a ray diagram to show the incident ray and its corresponding emergent ray.
Draw a diagram to show how a converging lens can form a real and enlarged image of an object.
Water is used in hot water bottles for fomentation. Give reason for this.
How is the kinetic energy of a moving cart affected if (i) its mass is doubled, (ii) its velocity is is made equal to speed of light.
Q. 9.
(a) The rear view mirror of a motor bike starts vibrating violently at some particular speed of the motor bike.
Why does this happen?
What is the name of the phenomenon taking place?
What could be done to stop the violent vibrations?
(b) A sound wave of wavelength 0.332 m has a time period of 10-3 s. If the time period is decreased to 10-4 s; calculate the wavelength and frequency of the new wave.
(c) (i) Define the terms: Amplitude and frequency for sound waves.
(ii) Name the subjective property of sound related to its frequency and of light related to its wavelength.
Q 10 The stem of a tuning fork is pressed against a table top. Answer the following questions :
(i) Would the above action produce any audible sound.
(ii) Does the above action cause the table to set into vibrations ?
(iii) If the answer above is yes, what type of vibrations are they ?
(iv) Under what conditions does the above action lead to resonance ?