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CAN A BODY HAVE A CONSTANT VELOCITY BUT VARYING SPEED ?
IF LENGTH L,TIME T AND ENERGY E ARE TAKEN AS BASE UNITS, FIND THE DIMENSIONS OF MOMENTUM ?
CAN A QUANTITY HAS DIMENSIONS STILL NO UNITS?
17.Gas molecules exert pressure on the surface of the container when they collide with the walls of the container. a. What is the expression for the pressure exerted by an ideal gas (1) b. Deduce the relationship between kinetic energy and absolute temperature of an ideal gas from the above expression (2) c. State law of equipartition of energy. What is the average kinetic energy of a monatomic gas molecule at temperature T. (1½) d. 30kg of water at 200C is mixed with 20kg of water at 300C. find the neutral temperature (1½)
17. First law of thermodynamics is a law of conservation of energy. a. Write the expression for first law of thermodynamics. (1) b. Distinguish between isothermal change and adiabatic change on the basis of first law of thermodynamics. (2) c. Deduce the work done during isothermal expansion. (2) d. What is the expression for work done during isothermal expansion?
15.Soap bubbles and liquid drops have excess pressure inside it. a. What is the reason for this excess pressure (½) b. Deduce the expression for excess pressure of a liquid drop. (3)
7. a. The motor of an automobile moving with a constant velocity is switched off. According to first law of motion it should continue its motion. But in practice it comes to rest. Why? (1) b. A bats man hits back a ball straight in the direction of bowler with out changing its initial speed of 12ms-1. If the mass of the ball is 0.15kg determine the impulse of the ball. (1½) c. A block of mass m is Sliding down an inclined plane of angle ?. If ? is the Coefficient of sliding friction between the block and inclined plane, what Is the acceleration of the body? (1½) d. Schematically represent the various forces acting on a car moving with a velocity v along a curved road which is banked at an angle ? with the horizontal (2)
If |A+B| = |A – B| where A and B are non zero vectors, what is the angle between them?
4. Four person sitting in the back seat of a car at rest, is pushing on the front seat. a) Does the car move. Why. b) State the law which help you to answer the above question. c) Give the significance of the law. d) Long jumpers take a long run before a jump. Why.
Small drops of a liquid are spherical while large drops are elliptical .Explain ?
13. A Girl tries to find the frequency of a tuning fork using Sonometer apparatus. a) What is the nature of wave produced in a sonometer. b) Explain why the paper rider thrown away at a particular resonating length. c) Explain how the girl finds the unknown frequency. 1+2+2=5
12. Vertical oscillation of loaded spring in water die out rapidly. a) Name the type of Oscillation here. b) How can you maintain the oscillation of loaded spring in water. c) A Girl swings in sitting position on a swing. How will the period of the swing be effected if she stands up.
3. a) Pick out the two scalar quantities in the following lists. Force, angular momentum, work, current, linear momentum, electric field, Velocity, magnetic moment b) The position of the particle is given by r= 3ti-2t2j+4k where t is in second i) Find v & a of the particle ii) Give the magnitude &direction of velocity of the particle at t=2 s?
If a magnifying glass magnifies the area of a small leaf 5 times.If the new area is 25mm square.Then what is the original area of the leaf? a, 1mm square b, 5mm square
In the absence of which disease does more people die?
what is given to patients before surgery for making them unconscious?
What is concave $ convex mirror?
define-subordinate conjuction
define-conjuction
What are the modes of reproduction in animals ?