# CBSE Class 11 Physics Sample Papers

Marks: 25
Duration: 1 hour

##### Section A: Each question carries 1 mark

Question 1: If two row- boats happen to sail -parallel, and close to each other, they experience a force which pulls them towards each other. Give reasons for it.

Question 2: Why Newtonâ€™s Law of gravitation is said to be universal Law?

Question 3: Why is Brownian motion significant?

Question 4: Why Length, mass and time is chosen as base quantities in mechanics?

Question 5: A harmonic oscillation is represented by y=0.34 cos(3000t+0.74), where y and t are in s. Deduce (i) the amplitude (ii) angular frequency (iii) the period and (iv) the initial phase.

##### Section B: Each question carries 2 marks

Question 1: What is binding energy of a satellite?

Question 2: A ball rolled on ice formed on the surface of a frozen lake with an initial speed of 1.8m/s goes on moving for a total distance of 12m before stopping. Find the value of the coefficient of rolling friction for ball-ice pair.

Question 3: A railway carriage moves over a straight track with acceleration a. A passenger in the carriage drops a stone. What is the acceleration of the stone w.r.t the carriage and the earth?

Question 4: Briefly explain on the basis of kinetic theory, why do the pressure of a gas is increased when the gas is heated?

##### Section C: Each question carries 3 marks

Question 1: Draw a diagram and with its help, show that surface energy per unit area numerically equals to the surface tension.

Question 2: Explain the principle of conservation of energy.