21.
What is a neuron?
a)
Particle released during radioactivity
b)
The anti – particle of neutron
c)
Basic unit of nervous system
d)
Basic unit of energy
22.
Matter waves are
a)
Electromagnetic waves
b)
Transverse waves
c)
Longitudinal waves
d)
De Broglie waves.
23.
When the
milk is churned vigorously the cream from it is separated out due to
a)
Gravitational force
b)
Frictional force
c)
Centrifugal force
d)
Centripetal force
24.
Which of the following is not caused by
atmospheric refraction of light?
a)
Twinkling of stars at night
b)
Sun appearing higher in the sky than it actually
is
c)
Sun becoming visible two or three minutes before
actual sunrise
d)
Sun appearing red at sunset.
25.
X – ң Rays are… waves.
a)
Longitudinal
b)
Transverse
c)
Electromagnetic
d)
Elastic
26.
The shape of a rain drop is spherical due to
a)
Viscosity
b)
Surface tension
c)
Elasticity
d)
Gravitation
27.
The penetrating powers of ά, ᵝ and ᵞ- radiations, in decreasing order are,
a)
ά,ᵝ,ᵞ
b)
ᵞ,ᵝ,ά
c)
ᵝ,ά,ᵞ
d)
ᵞ,ά,ᵝ
28.
The photoelectric effect is described as the
ejection of electrons from the surface of a metal when.
a)
It is heated
b)
It is placed in strong electric field
c)
Electrons of suitable velocity impinge on it
d)
Light of suitable wavelength falls on it.
29.
Assertion (a) light emitting diode (LED) lamps
offer longer service life as compared to
compact Fluorescent Lamps (CFL).
Reason
® light Emitting diodes (LED) lamps are more energy efficient as compared to
the compact fluorescent lamps (CFL).
Select
the correct answer using the codes given below:
a)
Both A and R are true and R explains A
b)
Both A and R are true but R is not the correct
explanation of A
c)
A is true and R is false
d)
A is false and R is true.
30.
By what mechanism does scent spread all over the
room if the lid is opened?
a)
Pressure in the bottle
b)
Compression from the bottle
c)
Diffusion
d)
Osmosis
ANSWERS
21.C
22.D
23.C
24.D
25.C
26.B
27.B
28.C
29.B
30.C