2018-10-01_Physics_For_You

SECTION A

1. A hard wire is broken by bending it repeatedly in

alternating directions. Why?

2. How does the boiling point of a liquid vary with

pressure?

3. Following are the graph of elastic materials. Which

one corresponds to that of brittle material?

Stress

Strain

(a)

Strain

(b)

Stress

Strain

(c)

Stress

4. Two balls A and B have radii in the ratio 1 : 4. What

will be the ratio of their terminal velocities in a

liquid?

5. Water rises in a capillary tube, whereas mercury

falls in the same tube. Why?

SECTION B

6. e breaking force for a wire is F. What will be the
   breaking force for
   (a) two parallel wires of the same size and
   (b) for a single wire of double the thickness?


7. By how much a rubber string of length
   10 m increases in length under its own weight
   when suspended vertically? Density of rubber
   = 1.5 × 10^3 kg m–3 ; Y = 5 × 10^8 N m–2 ; g = 10 m s–2.


8. An ideal uid ows through a pipe of circular cross
   section with diameters 5 cm and 10 cm as shown in
   the gure. Find the ratio of velocities of uid at A
   and B.


9. A small ball of mass m and density ρ is dropped
   in a viscous liquid of density ρ 0. Aer some time,
   the ball falls with a constant velocity. Calculate the
   viscous force on the ball.

CLASS XI

Mechanical Properties of Solids | Mechanical Properties of Fluids

Chapterwise practice questions for CBSE Exams as per the latest pattern and marking scheme

issued by CBSE for the academic session 2018-19.

GENERAL INSTRUCTIONS

(i) All questions are compulsory. (ii) Q. no. 1 to 5 are very short answer questions and carry 1 mark each.

(iii) Q. no. 6 to 12 are short answer questions and carry 2 marks each. (iv) Q. no. 13 to 24 are also short answer questions and carry 3 marks each.

(v) Q. no. 25 to 27 are long answer questions and carry 5 marks each. (vi) Use log tables if necessary, use of calculator is not allowed.

Time Allowed : 3 hours Maximum Marks : 70