Uploaded by guddumeghwar

XII 1st Test with solution

advertisement
XII Class Physics
Test-I (2nd August 2023)
Engr Kamran Ali Soomro
1. For diatomic gas Cp = ________________
(a) 1.5R
(b) 2.5R
(c) 3.5R
(d) 4R
2. For a gas Y = 1.25 then which of following is correct _____
(a) Cv = 2R
(b) Cp =3R
(c) Cp = 5R
(d) Cv = 1.5R
3. ∆𝑸 = ∆𝑼 holds for _______________ process
(a) Isobaric process
(b) Isothermal process
(c) Adiabatic Process
(d) Isochoric process
4. A system absorbs 150J of heat and performs 200J of work then its internal energy is
_______
(a) Increased by 50J
(b) Decreased by 50J
(c) Increased by 350J
XII Class Physics
Test-I (2nd August 2023)
Engr Kamran Ali Soomro
(d) Decreased by 350J
5. A system undergoes
(i)
Adiabatic expansion
(ii)
Isobaric expansion then
Change in internal energy is ∆𝑼 is ________
(a) For (i) positive , for (ii) negative
(b) For (i) negative, for (ii) positive
(c) For (i) zero , for (ii) positive
(d) For (i) positive , for (ii) positive
6. During Adiabatic compression _______________
(a) Temperature and pressure both decreases
(b) Temperature and pressure both increases
(c) Temperature decreases and pressure increases
(d) Temperature increases end pressure decreases
7. The electrostatic force between two spherical conductors having charges +4uC and -2uC is
‘F’ if conductors are touched together and then separated and kept at same distance then
new force will be ___
(a) F
(b) F/8
(c) F/4
(d) F/2
8. The free electron always experience electric force ___________
(a) In the direction of electric field
(b) In the opposite direction of electric field
(c) In the perpendicular direction of electric field
XII Class Physics
Test-I (2nd August 2023)
Engr Kamran Ali Soomro
(d) Tangent to the direction of electric field
9. Presence of dielectric between two point charges ________ the force, but presence of
dielectric plates of capacitors ______ the capacitance
(a) Decreases, increases
(b) Increases, decreases
(c) Decreases, will not affect
(d) Will not affect, increases
10. Find the K.E acquired by 5C charge while accelerating through potential different of
30Volt
(a) 150J
(b) 300J
(c) 600J
(d) 400J
11. The electric potential of small drop is 3Volt find the electric potential of big drop which
contains 8 drops ___________
(a) 3V
(b) 24V
(c) 12V
(d) 18V
(e) 10V
12. C1= 15uF and C2= 45uF capacitors are connected in series across 180V supply find the
voltage drop across C1 and C2 is _________
(a) V1 = 45V, V2= 135V
(b) V1= 135V, V2= 45V
(c) V1= 90V, V2= 90V
(d) V1= 60V, V2= 120V
XII Class Physics
Test-I (2nd August 2023)
Engr Kamran Ali Soomro
(e) V1= 120V, V2= 60V
13. A student has three capacitors each of capacitance 6uF then which capacitance can not be
obtained by using all capacitors
(a) 18uF
(b) 3uF
(c) 2uF
(d) 4Uf
14. The area of plates of capacitor is doubled and separation between plates is halved then
capacitance will be _____________
(a) Increased by four times
(b) Decreased by four times
(c) Remains same
(d) Becomes double
XII Class Physics
Test-I (2nd August 2023)
Engr Kamran Ali Soomro
(e) Becomes halved
15. A wire carries a current of 10A find the amount of charges flowing in wire in one minute
_____
(a) 50C
(b) 100C
(c) 30C
(d) 600C
q = I x t = 10 x 60 = 600C
16. When a wire is cut then its resistivity _________
(a) Increases
(b) Decreases
(c) Remains same
(d) Increases or decreases
17. A wire has resistance R and it is compressed and its radius is increased by three times then
its resistance will be _______
(a) R/3
(b) R/9
(c) R/27
(d) R/81
18. When battery is supplying current to external load then its e.m.f is ____________ the
terminal voltage
(a) Greater than
(b) Less than
(c) Equal to
(d) Half
19. E.m.f is similar to __________
(a) Potential energy
(b) Power
(c) Voltage
(d) Force
20. 8 ohm and 12 ohm resistors are connected in parallel, if current flowing in 12 ohm is 4A
then current in 8 ohm is _______
XII Class Physics
(a)
(b)
(c)
(d)
Test-I (2nd August 2023)
Engr Kamran Ali Soomro
6A
3A
2A
10A
21. The resistivity of semiconductor _____________
(a) Is independent of resistance
(b) Increased with increased in temperature
(c) Decreased with increased in temperature
(d) N.O.T
22. Find the current drawn by electric heater of 800Watt having resistance of 50 ohm ________
(a) 4A
(b) 6A
(c) 2A
(d) 3A
23. N A-1 m is equivalent to ____________
I. Tesla
II. Weber
III. Tesla m2
IV. Weber / m2
(a) I & I V only
(b) II & III only
(c) I & II only
(d) III & IV only
(e) II & IV only
XII Class Physics
Test-I (2nd August 2023)
Engr Kamran Ali Soomro
24. Relative Permeability (ur) of paramagnet is __________
(a) Slightly less than one
(b) Slightly greater than one
(c) Equal to one
(d) Much greater than one
25. A 5C charge particle is moving with a momentum of 20 kg m/s normal to magnetic field of
4Tesla find the radius of its trajectory ______________
(a) 1 m
(b) 2m
(c) 3m
(d) 4m
26. In steps up Transformer _____________
(a) Is< Ip, Vs>Vp
(b) Is>Ip, Vs<Vp
(c) Is=Ip , Vs = Vp
(d) Is>Ip , Vs >Vp
(e) Is<Ip, Vs<Vp
27. The core of Transformer is laminated so that __________
(a) Copper losses may be reduced
(b) Hysteresis losses may be reduced
(c) Eddy current losses may be reduced
(d) A.O.T
28. Lenz’s law is in accordance with __________
(a) Law of conservation of charge
(b) Law of conservation of energy
(c) Faraday’s law of electromagnetic induction
(d) Ampere’s law
29. A 50cm long conductor is moving perpendicular at speed of 100m/s in uniform magnetic
field of 0.5T find the e.m.f induced in conductor ____________
(a) 25V
(b) 12.5V
XII Class Physics
Test-I (2nd August 2023)
Engr Kamran Ali Soomro
(c) 50V
(d) 100V
(e) 75V
30. Particle in magnetic will not experience magnetic force if ____________
I.
Particle has no charge
II.
Particle is stationary
III.
Particle is moving perpendicular to magnetic field
IV.
Particle is moving parallel to magnetic field
(a) I &II
(b) I&III
(c) II & IV
(d) I, II & III
(e) I, II & IV
31. Magnetic field is usually represent by
I.
dot (.) notation
II.
cross (x) notion
(a) (I) denote into the page , (II) denote out of page
(b) (I) denote out of page, (II) denote into page
(c) (I) strong field , (II) denote weak field
(d) (I) uniform field , (II) non uniform field
32. Electric generator works on the principle of __________
(A) Faraday’s law
(B) Ampere’s law
(C) Lenz’s law
(D) Gauss’s law
33. When P-N junction diode is forward biased then __________
I.
It acts as closed switch
II.
Size of depletion region is reduced
III.
Size of depletion region is increased
IV.
Current will flow
(a) I & II only
(b) I & IV only
(c) I, II & IV
(d) I, III & IV
34. Addition of ________ impurity produces N-type material
(a) Trivalent
(b) Penta-valent
(c) Tetravalent
XII Class Physics
Test-I (2nd August 2023)
Engr Kamran Ali Soomro
(d) A.O.T
35. Half wave rectifier conduct for _______
(a) Portion of positive half cycle
(b) Portion of negative half cycle
(c) Entire positive half cycle and entire negative half cycle
(d) Either positive half cycle or negative half cycle
36. The maximum K.E of photoelectrons depends up on _____________
(I)
Intensity of light
(II)
Frequency of light
(III)
Work function of metal
(a) II only
(b) I & III only
(c) II & III only
(d) I & II only
37. For pair production the energy of light must be _______
(a) Greater than 1.02 keV
(b) Greater than 1.02 MeV
(c) Greater than 0.511 MeV
(d) Greater than 13.6 keV
38. Reverse process of photoelectric effect is __________
(a) Materialization of energy
(b) Compton’s effect
(c) Pair production
(d) X-rays production
39. Which types of radiation can perform pair production
(a) Infrared light
(b) X-rays
(c) Gama Rays
(d) Visible light
40. The wavelength of scattered photon is ___________ the wavelength of incident photon
(a) Less than
(b) Greater than
(c) Equal to
(d) N.O.T
41. All particle are accelerated through same p.d then which particle will posses longer DeBroglie wave length
(a) Electron
(b) Proton
(c) Alpha rays
(d) Beta rays
42. In photo electric phenomenon, if red color light is replaced with blue color light of same
intensity then what will be impact _______
I.
Numbers of photoelectrons will increased
II.
Maximum K.E of photoelectrons will increased
XII Class Physics
Test-I (2nd August 2023)
III.
IV.
Engr Kamran Ali Soomro
Numbers of photoelectrons remains same
Maximum K.E of photoelectrons will remains same
(a) I & IV
(b) II & III
(c) II only
(d) I only
43. When electron make transition from ni = 4 to nf= 2 then which series will be emitted
(a) Ballmer
(b) Paschen
(c) Lyman
(d) Pfund
(e) Bracket
44. The electron of hydrogen atoms is in 4th orbit then how many possible lines can be emitted
__
(a) 12
(b) 6
(c) 4
(d) 3
45. The longest wavelength emitted in Ballmer’s series is ___________
(a)
(b)
(c)
(d)
5
36𝑅
36
5𝑅
5𝑅
36
36𝑅
5
XII Class Physics
Test-I (2nd August 2023)
Engr Kamran Ali Soomro
46. The energy of electron of Hydrogen atom in 3rd excitation state is ___________
(a) -13.6eV
(b) -3.4eV
(c) -1.51eV
(d) -0.85eV
47. After Alpha disintegration the nucleon number is decreased by __________ and charge
number is decreased by ____________
(a) 4, 2
(b) 2,4
(c) 4,1
(d) 2,1
48. A nucleus 92X222 is transmuted into 90Y214 then there are _____________
(a) Two alpha emission only
(b) Two beta emission only
(c) Two alpha and one beta emission only
(d) Two alpha and two beta emission only
XII Class Physics
Test-I (2nd August 2023)
Engr Kamran Ali Soomro
49. __________ is used as tracer for liver
(a) Carbon
(b) Cobalt
(c) Iodine
(d) Phosphorus
50. A radio active sample has been decade to 12.5% in just 12 Hrs then its half life time is
_________
(a) 4 Hrs
(b) 6 Hrs
(c) 3 Hrs
(d) 2 Hrs
XII Class Physics
Test-I (2nd August 2023)
51. Which of following has high ionization power _________
(a) Alpha rays
(b) Neutron
(c) Gama Rays
(d) Beta rays
52. The product of decay constant and half life time is ______________
(a) Equal to one
(b) Equal to 0.693
(c) Equal to 0.707
(d) Equal to 0.5
53. The nucleon term is not used for ________
(a) Electron
(b) Proton
(c) Neutron
(d) Both a and b
(e) Both a and c
54. ___________ stores energy in magnetic field
(a) Resistor
(b) Inductor
(c) Capacitor
(d) Conductor
Engr Kamran Ali Soomro
XII Class Physics
Test-I (2nd August 2023)
Engr Kamran Ali Soomro
Download