Class- XI

                                                                                          Sample paper - 4

General Instructions:

1. All questions are compulsory. There are 37 questions in all.
2. This question paper has 4 sections: Section-A, Section-B, Section-C & Section-D.
3. Section A contains 20 questions of one mark.
4. Section-B contain 7 questions of 2 marks.
5. Section-C contains 7 questions of 3 marks
6. Section- D contains 3 questions of 5 marks each.
7. There is no overall choice. However internal choices are provided. You have to attempt only one of the choices in such questions.
8. Use of calculators is not permitted. However, you may use log tables if necessary.

 

SECTION - A

Question 1:                                                                                                                 

The Sun’s angular diameter is measured to be 1920′′. The distance D of the Sun from the Earth is 1.496 × 10¹¹ m. What is the diameter of the Sun?

 

Question 2:                                                                                                                           

Define average velocity.

 

Question 3:                                                                                                                           

What are vector quantities? Give some examples.

               

Question 4:                                                                                                                           

State Newton’s second law of motion.

 

Question 5:                                                                                                                          

What is the unit and dimension of angular momentum?

 

Question 6:                                                                                                                          

How can you calculate the value of ‘g’?

 

Question 7:                                                                                                                           

A bolt of mass 0.5 kg falls from the ceiling of an elevator moving down with an uniform speed of 10 m/s. It hits the floor of the elevator (length of the elevator = 5 m) and does not rebound. What is the heat produced by the impact? Would your answer be different if the elevator were stationary?

 

Question 8:                                                                                                                           

What is the gravitational potential energy associated with two particles separated by a distance r?

 

Question 9:                                                                                                                          

What do you understand by ‘Mean free path’?

                                                OR

State ‘law of conservation of momentum’.

 

Question 10:                                                                                                                           

What does Pascal’s law state?

Question 11:                                                                                                                          

What do you understand by periodic motion? How will you calculate the time period for one complete oscillation?

 

Question 12:                                                                                                                          

What do you understand by non-uniform motion?

                                                           OR

Define unit vector.

 

Question 13:                                                                                                                           

How do you define the term ‘stress’?

 

Question 14:                                                                                                                           

How many Pascals is equal to 1 atm?

 

Question 15:                                                                                                                          

What are the symbols and units for static and kinetic friction?

 

Question 16:                                                                                                                            

What is the ratio of c_p and c_v for polyatomic gases?

 

Question 17:                                                                                                                            

What is the acceleration due to gravity above the surface of the earth?

 

Question 18:                                                                                                                          

How many metres in 1 Astronomical unit?

 

Question 19:                                                                                                                            

What do you understand by instantaneous velocity?

 

Question 20:                                                                                                                            

If an object is in the circular motion, give formula for its centripetal acceleration.

 

SECTION - B

Question 21:                                                                                                                            

What is the acceleration due to gravity below the surface of the earth?

 

Question 22:                                                                                                                            

A structural steel rod has a radius of 10 mm and a length of 1.0 m. A 100 kN force stretches it along its length. Calculate (a) stress, (b) elongation, and (c) strain on the rod. Young’s modulus, of structural steel is 2.0 × 10¹¹ N-m^-2 .

 

Question 23:                                                                                                                            

The mass of the earth is 6 × 10²⁴ kg and that of the moon is 7.4 × 10²² kg. If the distance between the earth and the moon is 3.84 × 10⁵ km, calculate the force exerted by the earth on the moon. (Take G = 6.7 × 10^–11 N m² kg^-2)

 

Question 24:                                                                                                                            

A vessel contains two non-reactive gases: neon (monatomic) and oxygen (diatomic). The ratio of their partial pressures is 5:3. Estimate the ratio of (i) number of molecules and (ii) mass density of neon and oxygen in the vessel. Atomic mass of Ne = 20.2 u, molecular mass of O₂ = 32.0 u.

OR

A stone of mass 0.50 kg tied to the end of a string is whirled round in a circle of radius 2.0 m with a speed of 30 rev/min in a horizontal plane. What is the tension in the string? What is the maximum speed with which the stone can be whirled around if the string can withstand a maximum tension of 300N?

 

Question 25:                                                                                                                            

What is the pressure inside the drop of mercury of radius 2.00 mm at room temperature? Surface tension of mercury at that temperature (20 °C) is 4.65 × 10^–1 N-m^–1. The atmospheric pressure is 1.01 × 10⁵ Pa. Also give the excess pressure inside the drop.

 

Question 26:                                                                                                                            

A piece of copper having a rectangular cross-section of 10 mm × 12 mm is pulled in tension with 50,000 N force, producing only elastic deformation. Calculate the resulting strain?

 

Question 27:                                                                                                                           

An aircraft is flying at a height of 4000 m above the ground. If the angle subtended at a ground observation point by the aircraft positions 10.0s apart is 30⁰. What is the speed of the aircraft?

OR

A trolley of mass 300 kg moves with a uniform speed of 48 km/h on a frictionless track. A child of mass 30 kg runs on the trolley from one end to the other (15 m away) with a speed of 5 m/s relative to the trolley in a direction opposite to its motion, and jumps out of the trolley. What is the final speed of the trolley? How much has the trolley moved from the time the child begins to run?

 

SECTION - C

Question 28:                                                                                                                           

Define nodes and antinodes. Also, define fundamental and second harmonic mode of a wave.

 

Question 29:                                                                                                                           

What do you understand by ‘least count error’?

 

Question 30:                                                                                                                           

What is quasi-static process?

 

Question 31:                                                                                                                            

Define specific heat capacity of a substance.

 

Question 32:                                                                                                                            

Derive the theorem of perpendicular axes.

 

Question 33:                                                                                                                           

What do you understand by the condition of resonance?

 

Question 34:                                                                                                                          

A ball thrown vertically upwards with a velocity of 15ms^-1 from the top of a complex. The height of the point from where the ball is thrown is 30.0m from the ground. How high will the ball rise?

 

SECTION - D

Question 35:                                                                                                                           

A man stands on the edge of a cliff 500 m above the ground and throws a stone horizontally with an initial speed of 10 m/s. Neglecting air-resistance, find the time taken by the stone to reach the ground, and the speed with which it hits the ground. (Take g = 9.8 m/s²).

OR

A U-tube contains water and methylated spirit separated by mercury. The mercury columns in the two arms are in level with 12.0 cm of water in one arm and 15.0 cm of spirit in the other. What is the specific gravity of spirit?

 

Question 36:                                                                                                                          

Three bodies, a ring, a solid cylinder and a solid sphere roll down the same inclined plane without slipping. They start from rest. The radii of the bodies are identical. Which of the bodies reaches the ground with maximum velocity?

Question 37:                                                                                                                           

What is the theorem of parallel axes?

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