NEET TEST SERIES 130 PHYSICS

1. Density of the nucleus depends upon

a) Mass number
b) Atomic number
c) Number of neutronsd
d) None of these

2. Light of wavelength λ falls on metal having work functions hc/λ₀. Photoelectric effect will take place only if:

a) λ≥λ₀
b) λ≤λ₀
c) λ≥2λ₀
d) λ=4λ₀

3. The colours seen in the reflected white light from a thin oil film are due to

a) Diffraction
b) Interference
c) Polarisation
d) Dispersion

4. Which phenomenon leads us to the conclusion that light is transverse in nature?

a) refraction of light
b) diffraction of light
c) dispersion of light
d) polarization of light.

5. Photoelectric emission occurs only when the incident light has more than a certain minimum

a) power
b) wavelength
c) intensity
d) frequency

6. The threshold frequency of a certain metal is 3.3×10¹⁴ If light of frequency 8.2×10¹⁴Hz is incident on the metal, predict the cut off voltage for photoelectric emission. Given Planck’s constant, h=6.62×10^-34Js.

a) 2 V               
b) 4 V
c) 6 V
d)  8 V

8. Electric charges of 1μC, -1μC and 2μC are placed in air at the corners A, B and C respectively of an equilateral triangle ABC having length of each side 10 cm. The resultant force on the charge at C is

a) 0.9 N               
b) 1.8 N

c) 2.7 N               
d) 3.6 N

9. The potential due to an electric dipole varies as

a) r
b) 1/r
c) 1/r²
d) 1/r³

10. Two equal charges each are placed at a distance of 2a and a third charge -2q is placed at the mid-point. The potential energy of the system is

11. The capacitance of arrangement of four plates of area A at a distance  shown in figure is

12. At what angle of incidence will the light reflected from glass(μ=1.5) be completely polarised

a) 72.8°               
b) 51.6°
c) 40.3°               
d) 56.3°

13. Light is incident on a glass surface at polarising angle of 57.5°. Then the angle between the incident ray and the refracted ray is

a) 57.5°               
b) 115°
c) 205°
d) 145°

14. The work function for Al, K and Pt is 4.28 eV, 2.30 eV and 5.65 eV respectively. Their respective threshold frequencies would be

a) Pt>Al>K
b) Al>Pt>K
c) K>Al>Pt
d) Al>K>Pt

15. The linear momentum of a 3 MeV photon is

a) 0.01eVsm⁻¹
b) 0.02eVsm⁻¹
c) 0.03eVsm⁻¹
d) 0.04eVsm⁻¹

16. In an interference experiment, the ratio of the intensities of the bright and dark fringes is 16:1. The ratio of the amplitudes due to the two slits is

a) 3:1
b) 4:1
c) 5:1
d) 5:3

17. How many 10 μF capacitor must be connected in parallel to store a charge of 1 C with a potential of 100 V across the capacitors ?

a) 0.001 J
b) 0.01 J
c) 0.1 J
d) 1 J

18. How many 10 μF capacitor must be connected in parallel to store a charge of 1 C with a potential of 100 V across the capacitors ?

a) 100
b) 1000
c) 10000
d) 10

19. Four capacitors are connected in a circuit as shown in figure. The effective capacitance between P and Q will be

a) 10 μF
b) 5 μF
c) 2 μF
d) 7.5 μF

20. If the circumference of a sphere is 2 m, then the capacitance of the sphere in water would be (K_water=80)

a) 2700 pF
b) 2600 pF
c) 1800 pF
d) 2830 pF