PHYSICS TEST 4 - PAK ARMED FORCES TEST

QUIZ START

Results

congratulations!!

sorry! Better luck next time.

QUIZ START

#1. How many wave lengths of Kr^86 are contained in one meter?

1553164.13

652189.63

2347127.23

1650763.73

#2. When two bodies stick together after collision, the collision is said to be

Inelastic

Elastic

Partially elastic

None of the above

#3. A science student takes 100 observations in an experiment. Second time he takes 500 observations in the same experiment. By doing so the possible error becomes

5 time

1/5 times

Unchanged

none of these

#4. If the error in the measurement of radius of a sphere is 1% then the error in the measurement of volume will be

1.1%

#5. Light year is the unit of

Speed

mass

distance

time

#6. Debye is the unit of

density

rms velocity

electric dipole moment

magnetic dipole moment

#7. The unit of surface energy per unit area may be expressed as

Nm^-2

Nm^-1

Nm^2

#8. A particle is projected horizontally from a height of 10m. Time taken by it to hit the ground is

1 Sec

2 Sec

√2 Sec

σ3 Sec

#9. A force of 10N acts on a body of mass 2 kg for 2 sec. Rate of change of momentum of body is

5kg m/sec^2

10kg m/sec

15kg m/sec^2

none of these

#10. Sound waves having frequency in between 2KH and 4KH are called

Infrasonic

Ultrasonic

Threshold of hearing

Threshold of pain

#11. A body falling freely under the action of gravity has

constant weight

variable weight

maximum weight

no weight

#12. Keeping in view the Earth’s surface, the value of g on the equator is

zero

minimum

maximum

none of these

#13. A uniform plank of weight 20 N is 200 cm long and rests on a support that is 60 cm from one end. At what distance from that end must an 80 N weight be placed in order to balance the plank?

10 cm

20 cm

40 cm

50 cm

#14. Multimode step index fibre has a core of relatively larger diameter such is

125 μm

175 μm

50 μm

100 μm

#15. Single mode step index fibre has a very thin core of about diameter

5.5 μm

9.5 μm

5.0 μm

All of these

#16. How many phone calls can be carried by single mode step index fibre

2500

9600

14000

21000

#17. Multimode graded index fibre core has diameter of

40-200 μm

50-1000 μm

50-150 μm

50-300 μm

#18. Optical fibres are of

Five type

Two type

Three type

None of these

#19. A body of mass 100 gm is suspended from a spring of force constant 50 N/m. The maximum acceleration produced in the spring is

g/2

g/3

g/4

#20. The time period of a second’s pendulum on the surface of moon is found to be 2√6. The acceleration due to gravity on the surface of moon is

3.2 ms^-2

1.6 ms^-2

0.8ms^-2

0.6 ms^-2

#21. What will be the percentage change in the time period of a simple pendulum if its length is increased by 5%?

1/9%

2.5%

5.2%

#22. Which of the following quantities is non-zero at the mean position for a particle executing SHM?

Force

Acceleration

Velocity

Displacement

#23. The ratio of total energy of a harmonic oscillator to its average energy with respect to position will be

1 : 2

3 : 1

1 : 3

2 : 1

#24. If stress is increased beyond the elastic limit and change in solid is permanent, this behaviour is called

elasticity

plasticity

conductivity

insulator

#25. To get P-type semiconductor we add impurity from

3rd group

4th group

5th group

6th group

#26. 1st superconductor was discovered in year

1890

1930

1895

1911

#27. Triple point of water is

237.16° C

273.16 K

373.16° F

313.16 K

#28. Temperature of -273° C on Kelvin scale is

+23 K

+337 K

-273 K

0 K

#29. In the isothermal process, one of the following is constant

pressure

Volume

Temperature

heat energy

#30. The concept of entropy was introduced by the scientist

R Clausius

Newton

Kelvin

Carnot Sadi

#31. Carnot’s cycle is an example of

Irreversible process

Reversible process

All of these

None of these

#32. Voltage gain for operational amplifier is maximum when used as

Transistor

Non inverting amplifier

Power amplifier

Current amplifier

#33. The Boolean equation for NAND operation is written as

X = A + B

X = A.B

X = Ā.Ą

X = A+B

#34. In night switch op-amplifier is used as

inverting amplifier

none inverting amplifier

comparator

diode

#35. Which of the following does not obey Ohm’s law?

Copper

Diode

None

#36. A 5 ampere fuse wire can withstand a maximum power of 1 watt in the circuit. The resistance of the fuse wire is

0.04Ω

0.2Ω

5Ω

0.4Ω

#37. The Specific resistance of a wire

will depend on its length

will depend on its radius

will depend on the type of material of the wire

will depend on none of the above

#38. The working of a dynamo is based on the principle of

heating effect of current

magnetic effect of current

chemical effect of current

electromagnetic induction

#39. The magnitude of motional emf is given by

ε = - VBL

ε = VBL

ε = V/BL

ε = - L/VB

#40. What is SI unit of mutual inductance?

Farad

Coulomb

Henry

Ampere

#41. A photosensitive metallic surface has work function hf_0. If photons of energy 2 hf_0 fall on this surface, the electrons come out with a maximum velocity 4×10^6 ms^-1. When the photon energy is increased to 5 hf_0 then maximum velocity is

2×10^7 ms^-1

2×10^6 ms^-1

8×10^6 ms^-1

8×10^5 ms^-1

#42. A laser used to weld detached retinas emits light with a wavelength 652 nm in pulses that are of 20 ms duration. The average power during each pulse is 0.6 W. Find the energy in each pulse in eV and in a single photon

7.5×10^15 eV, 1.9eV

7.5×10^16 eV, 1.19eV

7.5×10^16 eV, 0.19eV

7.5×10^16 eV, 1.9eV

#43. When the incident frequency is f_o, K is the (KE)_max of the electrons emitted and φ is work function of the surface. If incident frequency is doubled new (KE)_max will be

2 K

2K-φ

2K+φ

2K+2φ

#44. A node voltage is at + 3V. Incident radiation has frequency 1.4×10^15 Hz and work function of the photoelectron cathode is 2.8 eV. Find the minimum and maximum KE of photon electron in eV

3, 6

0, 3

0.6

2.8, 5.8

#45. In proton – proton cycle, number of protons consumed are

Two

Four

Six

Eight

#46. One curie is equal to

3.7 × 10^10 Bq

3.6 × 10^10 Bq

3.7 × 10^-10 Bq

#47. The mass density of a nucleus varies with mass number A as

A^2

Constant

1/A

#48. The energy released in a typical nuclear fusion reaction is approximately

25 MeV

200 MeV

800 MeV

1050 MeV

#49. If a glass slab is placed in the path of a converging beam of light. The point of convergence of light

moves away from the glass slab

moves towards the glass slab

remains at the same point

moves straight

#50. The angle with the horizontal at which an underwater swimmer will see the setting sun is

91°

32°

49°

69°

Finish

Results

#1. How many wave lengths of Kr^86 are contained in one meter?

#2. When two bodies stick together after collision, the collision is said to be

#3. A science student takes 100 observations in an experiment. Second time he takes 500 observations in the same experiment. By doing so the possible error becomes

#4. If the error in the measurement of radius of a sphere is 1% then the error in the measurement of volume will be

#5. Light year is the unit of

#6. Debye is the unit of

#7. The unit of surface energy per unit area may be expressed as

#8. A particle is projected horizontally from a height of 10m. Time taken by it to hit the ground is

#9. A force of 10N acts on a body of mass 2 kg for 2 sec. Rate of change of momentum of body is

#10. Sound waves having frequency in between 2KH and 4KH are called

#11. A body falling freely under the action of gravity has

#12. Keeping in view the Earth’s surface, the value of g on the equator is

#13. A uniform plank of weight 20 N is 200 cm long and rests on a support that is 60 cm from one end. At what distance from that end must an 80 N weight be placed in order to balance the plank?

#14. Multimode step index fibre has a core of relatively larger diameter such is

#15. Single mode step index fibre has a very thin core of about diameter

#16. How many phone calls can be carried by single mode step index fibre

#17. Multimode graded index fibre core has diameter of

#18. Optical fibres are of

#19. A body of mass 100 gm is suspended from a spring of force constant 50 N/m. The maximum acceleration produced in the spring is

#20. The time period of a second’s pendulum on the surface of moon is found to be 2√6. The acceleration due to gravity on the surface of moon is

#21. What will be the percentage change in the time period of a simple pendulum if its length is increased by 5%?

#22. Which of the following quantities is non-zero at the mean position for a particle executing SHM?

#23. The ratio of total energy of a harmonic oscillator to its average energy with respect to position will be

#24. If stress is increased beyond the elastic limit and change in solid is permanent, this behaviour is called

#25. To get P-type semiconductor we add impurity from

#26. 1st superconductor was discovered in year

#27. Triple point of water is

#28. Temperature of -273° C on Kelvin scale is

#29. In the isothermal process, one of the following is constant

#30. The concept of entropy was introduced by the scientist

#31. Carnot’s cycle is an example of

#32. Voltage gain for operational amplifier is maximum when used as

#33. The Boolean equation for NAND operation is written as

#34. In night switch op-amplifier is used as

#35. Which of the following does not obey Ohm’s law?

#36. A 5 ampere fuse wire can withstand a maximum power of 1 watt in the circuit. The resistance of the fuse wire is

#37. The Specific resistance of a wire

#38. The working of a dynamo is based on the principle of

#39. The magnitude of motional emf is given by

#40. What is SI unit of mutual inductance?

#41. A photosensitive metallic surface has work function hf_0. If photons of energy 2 hf_0 fall on this surface, the electrons come out with a maximum velocity 4×10^6 ms^-1. When the photon energy is increased to 5 hf_0 then maximum velocity is

#42. A laser used to weld detached retinas emits light with a wavelength 652 nm in pulses that are of 20 ms duration. The average power during each pulse is 0.6 W. Find the energy in each pulse in eV and in a single photon

#43. When the incident frequency is f_o, K is the (KE)_max of the electrons emitted and φ is work function of the surface. If incident frequency is doubled new (KE)_max will be

#44. A node voltage is at + 3V. Incident radiation has frequency 1.4×10^15 Hz and work function of the photoelectron cathode is 2.8 eV. Find the minimum and maximum KE of photon electron in eV

#45. In proton – proton cycle, number of protons consumed are

#46. One curie is equal to

#47. The mass density of a nucleus varies with mass number A as

#48. The energy released in a typical nuclear fusion reaction is approximately

#49. If a glass slab is placed in the path of a converging beam of light. The point of convergence of light

#50. The angle with the horizontal at which an underwater swimmer will see the setting sun is

❌ Your Wrong Attempts: