Question Bank for Physics in Class XI standard : Just Exam

1. Physical World - Quiz

1. Match the following :

A	Scientist	B	Country of Origin
1	Archimedes	a	Italy
2	Galileo	b	Japan
3	Curie	c	Germany
4	Heinsenberg	d	France
5	Yukawa	e	Greece

a) 1-e, 2-a, 3-d, 4-c, 5-b
b) 1-c,2-a, 3-b, 4-c, 5-d
c) 1-c, 2-e, 3-b, 4-a, 5-d
d) 1-b, 2-c, 3-a, 4-e, 5-d

2. Inverse square law of distance is followed by
a) gravitational forces
b) electromagnetic forces
c) both (a) and (b) above
d) neither (a) nor (b)

2. Units and Measurements - Quiz

1. The dimension of 1/2 ∈₀E², where ∈₀ is permittivity of free space and E is electric field, is
a) ML²T^-2
b) ML^-1T^-2
c) ML²T^-2
d) MLT^-1

2. Two spherometers A and B have the same pitch. A has 100 divisions on periphery of its circular disc and B has 200 divisions on periphery of its circular disc. Then
a) Both A and B have same least count
b) L.C. of A is twice the L.C. of B
c) L.C. of A is half the L.C. of B
d) Nothing can be said

3. Motion in a Straight Line - Quiz

1. If x denotes displacement in time t and x = a cos t, then acceleration is
a) a cos t
b) -a cos t
c) a sin t
d) -a sin t

2. If the distance covered is zero, then displacement
a) Must be zero
b) May or may not be zero
c) Cannot be zero
d) Depends upon the particle

4. Motion in a Plane - Quiz

1. A particle of mass m is projected with a velocity υ making an angle of 30⁰ with the horizontal. The magnitude of angular momentum of the projectile about the point of projection when the particle is at its maximum height h is
a) √3/2 mυ²/g
b) zero
c) mυ³/√g
d) √3/16 mυ³/g

2. A projectile has initially the same horizontal velocity as it would if it had moved from rest with uniform acceleration of 3 ms^-2 for 0.5 minutes. If the maximum height reached by it is 80 m, then the angle of projection is (Take g =10 ms^-2)
a) tan^-1 (3)
b) tan^-1(3/2)
c) tan^-1(4/9)
d) tan^-1(9/4)

5. Laws of Motion - Quiz

1. A 30 kg block rests on a rough horizontal surface. A force of 200 N is applied on the block. The block acquires a speed of 4 m/s starting from rest in 2 s. what is the value of coefficient of friction?
a) √3/10
b) 10/3
c) 0.47
d) 0.185

2. In the above question, the force of limiting friction is
a) 3 N
b) 5 N
c) 4 N
d) Zero

6. Work, Energy and Power - Quiz

1. The speed c reached by a car of mass m in travelling a distance x, driven with constant powers P, is given by
a)
b)

2. The potential energy of a 1 kg particle free to move along the X-axis is given by

The total mechanical energy of the particle is 2J. Then the maximum speed (in m/s) is
a) √2
b) 1/ √2
c) 2
d) 3/√2

7. System of Particles and Rotational Motion - Quiz

1. A thin uniform rod, pivoted at O, is rotating in the horizontal plane with constant angular speed ω, as shown in the (figure). At time t =0, a small insect starts from O and moves with constant speed v with respect to the rod towards the another end. It reaches the end of the rod at t = T and stops. The angular speed of the system remains ω throughout. The magnitude of the torque

on the system about O, as a function of time is best represented by which plot in (figure)

a)

b)

c)

d)

2. A flywheel of moment of interia 3 x 10² kg m² is rotating with uniform angular speed of 4.6 rad s^-1. If a torque of 6.9 x 10² Nm retards the wheel, then the time in which the wheel comes to rest is
a) 1.5 s
b) 2 s
c) 0.5 s
d) 1 s

8. Gravitation - Quiz

1. A tunnel is dug along the diameter of the earth (radius R and mass M). There is a particle of mass m at the centre of the tunnel. The minimum velocity is given to the particle so that it just reaches to the surface of the earth is
a) $\sqrt{\frac{GM}{R}}$
b) $\sqrt{\frac{GM}{2R}}$
c) $\sqrt{\frac{2GM}{R}}$
d) it will reach with the help of a negligible velocity

2. A point mass m is released from rest at a distance 3R from the centre of an thin-walled hollow sphere of radius R and mass M as shown. The hollow sphere is fixed in position and the only force on the point mass is the gravitational attraction of the hollow sphere. There is a very small hole in the hollow sphere through which the point mass falls as shown. The velocity of a point mass when it passes through point P at a distance R/2 from the centre of the sphere is

a) $\sqrt{\frac{2GM}{3R}}$
b) $\sqrt{\frac{5GM}{3R}}$
c) $\sqrt{\frac{25GM}{24R}}$
d) none of these

9. Mechanical Properties of Solids - Quiz

1. Two roads f different materials, having coefficients of linear expansions α₁ and α₂ and young modulii Y₁ and Y₂, are fixed between two rigid walls. The rods are heated to the same temperature, there is no bending of rods. If α₁ : α₂ = 2/3 and equal stress is developed in the two rods, then Y₁ / Y₂ = 3/2.
a) True
b) False

2. Two wires of the same material and length but diameters in the ratio 1:2 are stretched by the same force. The potential energy per unit volume for the two wires when stretched will be in the ratio
a) 16 :1
b) 4:1
c) 2:1
d) 1:1

10. Mechanical Properties of Fluids - Quiz

1. A U-tube is partially filled with water. Oil which does not mix with water is next poured into one side untill water rises by 25 cm on the other side. If the density of oil be 0.8, the oil level will stand higher than water level by
a) 6.25 cm
b) 12.50 cm
c) 31.75 cm
d) 62.50 cm

2. Water from a tap (at the end of a horizontal pipe) emerges vertically downwards with an initial speed of 1.0 ms^-1. The cross-sectional area of the tap is 10^-4 m².Assume that the pressure is constant throughout the stream of water and the flow is steady. The cross-sectional area of the stream 0.15 m below the tap is (g = 10 ms^-2).
a) 5.0 x 10^-4 m²
b) 1.0 x 10^-5 m²
c) 5 x 10^-5 m²
d) 2.0 x 10^-5 m²

11. Thermal Properties of Matter - Quiz

1. Water equivalent of a body is equivalent to the product of _________and _____of the body.
a) Mass ; specific heat
b) Specific heat ; mass
c) Both a and b
d) None of these

2. Hot water cools from 60⁰ C to 50⁰ in the first 10 minutes and to 42⁰C in the next 10 minutes. The temperature of the surroundings is
a) 10⁰C
b) 5⁰C
c) 15⁰C
d) 20⁰C

12. Thermodynamics - Quiz

1. A carnot engine havinf efficiency of η = 1/10 as heat engine, is used as a refrigerator. If the work done on the system is 10J, the amount of energy absorbed from the reservoir at lower temperature is
a) 100J
b) 99J
c) 90J
d) 1J

2. In the V-T diagram shown in fig. . Ehat is the relation between P₁ and P₂?

a) P₂ = P₁
b) P₂>P₁
c) P₂1
d) cannot say

13. Kinetic Theory - Quiz

1. The temperature at which oxygen molecular have the same rms speed as that of hydrogen molecules at 300K is
a) 600K
b) 2400K
c) 1200K
d) 4800K

2. When an ideal gas is taken from state a to b, along a path acb, 84kJ of heat flows into the gas and the gas does 32 kJ of work. The following conclusions are drawn. Mark the one which is not correct

a) If the work done along the path adb is 10.5 kJ, the heat that will flow into the gas is 62.5 kJ.
b) When the gas is returned from b to a along the curved path, work done on the gas is 21 kJ, and the system absorbs 73 kJ of heat.
c) If U_d = 42kJ, and the work done along the path adb is 52.5 kJ
d) If U_a , U_d = 42 kJ, heat absorbed in the process db is 10 kJ

14. Oscillations - Quiz

1. A police car with a siren frequency 8 KHz is moving with uniform velocity 36Km/hr towards a tall building which reflects the sound waves. The speed of sound in air is 320m/s . The frequency of the siren heard by the car driver is
a) 8.50 kHz
b) 8.25 kHz
c) 7.75 kHz
d) 7.50 kHz

2. A block of mass 10kg is in equilibrium as shwon in fig. Initially the spring have same stretch. If the block is displaced in vertical direction by a small amount, then the angular frequency of resulting motion is (assume strings are never slack)

a) $10\sqrt{2}$
b) $10\sqrt{5}$
c) $5\sqrt{2}$
d) $5\sqrt{2}$

15. Waves - Quiz

1. A closed organ pipe has a frequency n. If its length is doubled and radius is halved, its frequency nearly becomes
a) halved
b) doubled
c) trebled
d) quadrupled

2. A metal rod 40cm long is dropped on to a wooden floor and rebounds into air. Compressional waves of many frequencies are thereby set up in the rod. If the speed of compressional waves in the rod in 5500m/s, what is the lowest frequency of compressional waves to which the rod resonates as it rebounds?
a) 675 Hz
b) 6875 Hz
c) 16875 Hz
d) 0 Hz

16. Scalar and Vector - Quiz

1. In an equilateral triangle ABC, AL, BM, and CN are medians. Forces along BC and BA represented by them will have a resultant represented by
a) 2AL
b) 2BM
c) 2CN
d) AC

2. The sum and difference of two perpendicular vectors of equal length are
a) Perpendicular to each other and of equal length
b) Perpendicular to each other and of different lengths
c) Of equal length and have an obtuse angle between them
d) Of equal length and have an acute angle between them

17. Conservation of momentum and Collision - Quiz

1. A body is hanging from a rigid support by an inextensible string of length l. It is struck inelastically by an identical body of mass m moving with horizontal velocity v = $\sqrt{2gl}$, the tension in the string increases just after strinking by
a) mg
b) 3mg
c) 2mg
d) none of these

2. A cannon of mass 1000 kg located at the base of an inclined plane fires a shell of mass 50 kg in horizontal direction with velocity 180 km/h. The angle of inclination of the inclined plane with horizontal is 45⁰. The coefficient of friction between the cannon and inclined plane is 0.5. The maximum height, in metre, to which the cannon can ascend the inclined plane as a result of recoil is
a) $\frac{5}{6}$
b) $\frac{5}{24}$
c) $\frac{5}{12}$
d) none of these

18. Rotational Dynamics - Quiz

1. Each pulley in Figure has radius r and moment of inertia I. The acceleration of the block is

a) $\frac{(M-m)g}{(M+m+\frac{2I}{r^{2}})}$
b) $\frac{(M - m)g}{(M + m - \frac{2I}{r^{2}})}$
c) $\frac{(M-m)g}{(M+m+\frac{I}{r^{2}})}$
d) $\frac{(M-m)g}{(M+m-\frac{I}{r^{2}})}$

2. In Figure, the bar is uniform and weighing 500 N. How large must W be if T₁ and T₂ are to be equal ?

a) 500 N
b) 300 N
c) 750 N
d) 1500 N

19. Fluid Dynamics - Quiz

1. We have two different liquids A and B whose relative densities are 0.75 and 1.0, respectively. If we dip solid objects P and Q having relative densities 0.6 and 0.9 in these liquids, then
a) P floats in A and Q sinks in B
b) P sinks in A and Q floats in B
c) P floats in B and Q sinks in A
d) P sinks in B and Q floats in A

2. Equal masses of three liquids are kept in three identical cylindrical vessels A, B and C. Their densities are ρ_A , ρ_B and ρ_C with ρ_A < ρ_B < ρ_C. The force on the base will be
a) maximum in vessel A
b) maximum in vessel B
c) maximum in vessel C
d) same in all the three vessels

Color

Physics [Class XI]

Class/Course - Class XI

Subject - Physics

Total Number of Question/s - 6437