## CLASS 11 PHYSICS – PRACTICE PAPER FOR ANNUAL EXAM

SESSION ENDING EXAMINATION

CLASS XI

PHYSICS

M.MARKS:70

TIME 3 HRS

General Instructions:

• All questions are compulsary
• There are 30 questions in total. Questions 1 to 8 carry 1 mark each. Questions 9 to 18 carry 2 marks each. Questions 19 to 27 carry 3 marks each and questions 28 to 30 carry 5 marks each.
• Use of calculators is not permitted.

******Choices are avoided as this is a question paper meant for practice ***********

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## Motion in a vertical circle and conservation of energy

A stone  tied to a string of length l is whirled around a vertical circle with the other end of the string at the centre. At a certain instant of time the stone is at the lowest position and has a speed u. What is the magnitude of change in its velocity as it reaches a position where the string is horizontal?

Let’s assume that the potential energy at the lowest position be zero. So, when the string is horizontal, the stone has risen by a vertical height l, the length of the string which is also the radius of the vertical circle.

A bullet of mass m is fired with a velocity v and strikes a a block of mass M suspended by a string of length L.
the bullet gets embedded in the block. What is the angle the the block makes due to the impact?

Why planets revolve around their own axis?

At time t=0 a ball is projected with a velocity = 60 m/s at 60 degrees form x axis.find the times when the velocity will make angle of 45 degree from x axis?

Suppose that, while lying on a beach near the equator watching the Sun set over a calm ocean, you start a stopwatch just as the top of the Sun disappears.You then stand, elevating your eyes by a height H = 1.70 metres, and stop the watch when the top of the Sun again disappears, If the elapsed time is t=11.1 s, what is the radius r of earth?

## Addition of vectors – can you add 3 unit vectors to get a unit vector ?

“Can you add 3 unit vectors to get a unit vector ? discuss in terms of velocity, force etc”

-Sindhuja posted

## Class XI Physics Chapter wise Revision Test – Gravitation and Waves

PHYSICS TESTPAPER

CLASS XI

GRAVITATION AND WAVES

Instructions

Questions 1 to 5 carries one mark each

Questions 5 to 10 carries 2 marks each

Questions 10 to 15 carries 3 marks each

Questions 16 and 17 carries 5 marks each

1. What are mechanical waves?
2. The time period of a vibrating source producing sound is 0.01 s. If the velocity of sound is 340 ms -1 calculate wave length
3. State the principle of superposition of waves
4. Why is gravitational potential energy negative?
5. What is geosynchronous satellite?
6. Derive a relation between wave velocity, frequency and wavelength
7. What are transverse and longitudinal wave motions? Give an example for each type
8. What is the effect of pressure on the speed of sound? Justify your answer.
9. What is a progressive wave? Write an expression which represents a progressive wave.
10. State the conditions necessary for a satellite to appear stationary.
11. Define orbital velocity. Derive an expression for it.
12. Define acceleration due to gravity. Show that the value of ‘g’  decreases with altitude or height
13. State the laws of vibrations of stretched strings.
14. Derive an expression for the escape velocity of a satellite projected from the surface of the earth.
15. What is the maximum value of potential energy that can be possessed by a heavenly body? Give the general expression for potential energy of an object  near the surface of earth
16. State Kepler’s law of planetary motion. Deduce Newton’s law of gravitation from Kepler’s law.
17. (a)What is Doppler Effect?  (b) Derive an expression for the apparent frequency when a source moves towards a stationary observer.  (c) A policeman on duty detects a drop of 15% in the pitch of the horn of a motor car as it crosses him. Calculate the speed of car, if the velocity of sound is 330 m/s