If a charged particle (+ q) is projected with certain velocity parallel to the magnetic field, then it will
trace helical path
trace circular path
continue its motion without any change
come to rest instantly
Optical fibres, though bent in any manner, allows light to pass through. What is the inference that one can draw from it?
The concept that light travels in straight path is wrong
Light can flow through the optical fibres
Light can travel through the fibres because of their ductility
Light can travel through the fibres due to multiple total internal reflections
Match List-I with List-II
List I (Physical quantity)
List II (Unit)
(a) - 3, (b) - 1, (c) - 2, (d) - 4
(a) - 3, (b) - 2, (c) - 1, (d) - 4
(a) - 4, (b) - 2, (c) - 1, (d) - 3
(a) - 4, (b) - 1, (c) - 2, (d) - 3
A ray of light when refracted suffers change in velocity. In this context, which one among the following statements is correct?
Velocity increases as the ray passes from a rarer to a denser medium
Velocity decreases as the ray passes from a denser to a rarer medium
Velocity decreases as the ray passes from a rarer to a denser medium
Change of velocity does not depend on the nature of medium
An object is placed 10 cm in front of a convex lens of focal length 15 cm. 'The image produced will be
Real and magnified
Virtual and magnified
Virtual and reduced in size
Real and reduced in size
Why is Graphite used in electrolytic cells?
Graphite is soft and can be easily moulded into electrodes
Graphite is made of layers of carbon atoms which can slide
Graphite is inert to most ofthe chemicals and remains intact in electrolytic cells
Graphite is a good conductor of electricity
A solid is melted and allowed to cool and solidify again. The temperature is measured at equal intervals of time. The graph below shows the change of temperature with time.
The part of the curve that is practically horizontal is due to
latent heat given away by the liquid
specific heat given away by the liquid
thermal capacity changes with time keeping temperature constant
change in density during transformation
The product of conductivity and resistivity of a conductor
depends on pressure applied
depends on current flowing through conductor
is the same for all conductors
varies from conductor to conductor
We use CFL to save electrical energy and to provide sufficient light. The full form of CFL is
Condensed filament light
Compact filament lamp
Condensed fluorescent lamp
Compact fluorescent lamp
When the sun is 30° above the horizon, shadow of one tree is 17 .3 m long. What is the height of this tree?
20 m
17.30 m
10 m
1.73 m