work sheet for class xi

ARMY PUBLIC SCHOOL GOLCONDA

PHYSICS WORK SHEET

CLASS –XI

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1.       What is the difference between A^o and A.U.?

2.       Define S.I. unit of solid angle?

3.       Name physical quantities whose units are electron volt and Pascal?

4.       When a planet X is at a distance of 824.7 million kilometers from earth its angular diameter is measured to be 35.72¹¹ of arc. Calculate the diameter of ‘X’.

5.       A radar signal is beamed towards a planet from the earth and its echo is received seven minutes later. Calculate the velocity of the signal, if the distance between the planet and the earth is 6.3x1010m?

6.       The blades of an aero plane propeller are rotating at the rate of 600 revolutions per minute. Calculate its angular velocity.

7.       A body of mass m is thrown with velocity ' ' υ at angle of 30o to the horizontal and another body B of the same mass is thrown with velocity υ at an angle of 60o to the horizontal. Find the ratio of the horizontal range and maximum height of A and B?

8.       What will be the effect on horizontal range of a projectile when its initial velocity is doubled, keeping the angle of projection same?

9.       Draw displacement time graph for a uniformly accelerated motion? What is its shape?

10.   A car moving on a straight highway with speed of 126km/hr. is brought to stop within a distance of 200m. What is the retardation of the car and how long does it take for the car to stop?

11.   Displacement of a particle is given by the expression x = 3t2 + 7t – 9, where x is in meter and t is in seconds. What is acceleration?

12.   A bird is sitting on the floor of a wire cage and the cage is in the hand of a boy. The bird starts flying in the cage. Will the boy experience any change in the weight of the cage?

13.   Why does a cyclist lean to one side, while going along curve? In what direction does he lean?

14.   A thief jumps from the roof of a house with a box of weight W on his head. What will be the weight of the box as experienced by the thief during jump?

15.   State and prove the principle of law of conservation of linear momentum?

16.   A man weighs 70kg. He stands on a weighting machine in a lift, which is moving  (a) Upwards with a uniform speed of 10m/s.  (b) Downwards with a uniform acceleration of 5m/s2. (c) Upwards with a uniform acceleration of 5m/s2. Take g = 9.8m/s2.

16.What would be the readings on the scales in each case what would be the reading if the lift mechanism failed and it came down freely under gravity?

17.   How is centripetal force provided in case of the following? (i) Motion of planet around the sun, (ii) Motion of moon around the earth. (iii) Motion of an electron around the nucleus in an atom.

18.   Force of 16N and 12N are acting on a mass of 200kg in mutually perpendicular directions. Find the magnitude of the acceleration produced?

19.   State Newton’s second, law of motion. Express it mathematically and hence obtain a relation between force and acceleration.

20.   Derive the expression for the potential energy stored in a spring?

21.   A shot fired from cannon explodes in air. What will be the changes in the momentum and the kinetic energy?

22.   A body of mass 2kg initially at rest moves under the action of an applied force of 7N on a table with coefficient of kinetic friction = 0.1. Calculate the(1) Work done by the applied force in 10s (2) Work done by the friction in 10s (3) Work done by the net force on the body in 10s.

23.   A particle moves along the x – axis form x = 0 t x = 5m influence of force given by F = 7 – 2x + 3x2. Calculate the work done in doing so.

24.   If the momentum of the body increases by 20% what will be the increase in the K.E. of the body?

25.   What is work done in holding a 15kg suitcase while waiting for a bus for 15 minutes?

26.   A body of mass 3kg makes an elastic collision with another body at rest and continues to move in the original direction with a speed equal to one – third of its original speed. Fine the mass of the second body.

27.   Prove that in an elastic collision in one dimension the relative velocity of approach before impact is equal to the relative velocity of separation after impact?

28.   State and prove work energy theorem analytically?

29.   Draw a graph showing variation of potential energy, kinetic energy and the total energy of a body freely falling on earth from a height h?

30.   Define Gravitational potential energy hence deduces an expression for gravitational potential energy of a body placed at a point sear the surface of earth?

31.   A body is weightless at the centre of earth. Why?

32.   The earths mass is 80 times that of moon and their diameters are in the ratio 4:1 respectively. What is the value of g on moon?

32.

NOTE:-         

·         This work sheet covers all the chapters in part –I physics.

·         Solve this work sheet in your physics fair note book.

·         Date of submission:                14^th Oct, 2014.