PHYSICS – 2
OUR UNIVERSE
– GRAVITATION:
1) Copernican theory is also known as
_____________________________
Ans
: Helio centric theory
2) Mass (M) of earth is
_________
Ans:
6 x 1024 Kg
3) Radius ® of earth is ______________
Ans: 6.4 x 106 m
4) the value of ‘g’ on the earth in S.I. system is
_____________
Ans
: 9.8 m/s2
5) The value of ‘g’ on the moon is ____________
Ans
: 1.67 m/s 2
6) the value of ‘g’ on the sun is ______________
Ans
: 27.4 m/s2
7) The force that keeps the planets in their orbits is
the _______ of the sun
Ans
: gravitational force
8) The moon makes one revolution about the earth in
______ days
Ans
: 27.3
9) The distance of the moon from the earth is about
___________ KMs
Ans:
3.85 x 105
10) The basis of Newton’s Laws of universal gravitation
is ___________
Ans
: Kepler’s Laws
11) Orbiting around the sun in circular orbits is first
proposed by _______
Ans
: Copernicus
12) The path of a planet around the sun is ________
Ans
: elliptical
13) The value of ‘g’ at the poles of the earth is _______
Ans
: maximum
14) The value of ‘g’ at the equator is __________
Ans
: minimum
15) 1 Kilogram weight weight on earth is equal to
_________
Ans
: 9.8 Newtons
16) The orbital velocity required for an object to go
round the earth is _______
Ans
: around 8 km/sec
17) Escape velocity of an object, to go out of the
gravitational pull of the earth is _____
Ans
: 11.2 Km/sec
18) Ecape velocity of an object, to go out of the
gravitational pull of the sun is ________
Ans
: about 42 KM/sec
19) Mass of a body anywhere in the world is __________
Ans
: same
DYNAMICS:
1) Circular
motion is a special case of ______
Ans : rotator motion
2) If the string
of whirling stone is cut, the stone moves in ___________
Ans: tangential
3) In a uniform
circular motion the angular velocity is __________
Ans : constant
4) Centre seeking
force is called as ______________
Ans : Centripetal force
5) Centrifugal
force means __________
Ans : centre fleeing force or a
force directed away from the centre
6) Newton’s laws
are valid in _______ frame of reference.
Ans : inertial
7) The study of
motion of a body under the action of force is called __________
Ans : dynamics
8) Examples for
translator motion ______________
Ans (1) motionof a flywheel,(2) motion of earth about its axis
9) Examples for
oscillatory motion ______________
Ans : (1) motion of a pendulum
(2) motion of mass attached to a
string
10) Earth goes
round the sun because of _______ of attraction between them.
Ans : gravitational force
11) The
gravitational force of attraction provides the necessary ______ for a satellite
revolving round a planet.
Ans : centripetal force
12) When electron
revolves round the nucleus in an atom, the centripetal force is provided by the
_________ of attraction between them.
Ans : electro static force
13) Centrifugal
force is also known as ____________
Ans : fictitious force or pseudo
force
14) A _______________ is used to separate
particles of higher mass from the lower mass in a given mixture.
Ans : centrifuge
15) When a
running car takes a sudden left turn, a man sitting in the back seat falls to
the right due to _______ of direction.
Ans : inertia
16) The magnitude
of centripetal force and centrifugal force is ______
Ans: same
17) ________
depends on the expected speed of vehicle and the radius of the curvature of the
road.
Ans: Banking angle
18) _______ is a
body orbiting around another body.
Ans : Satellite
19) Earth goes
round the sun because of ________
Ans : gravitational force of
attraction
20) The
domestic churner works on the principle
of a __________
Ans : centrifuge
21) The natural
satellite of earth is ________
Ans : Moon
22) Satellites
and space stations used for study of planets, stars and _____ in the universe.
Ans : galaxies
23) “The orbinal
velocity of an artificial satellite is ________ km/sec.
Ans : about 8 and less than 11
24) ____________
force is a pull on the body towards the centre of a circle.
Ans : Centripetal
25) The principle
of launching an artificial satellite into orbit is to sufficient intial _____
speed such that it revolves round the earth at the choosen height.
Ans : horizontal
26) The device
used to separate particles of higher mass from those of lower mass in a given
mixture _______
Ans : centrifuge
27) A car moves
on a curved but level road. The
necessary centripetal force on the car is provided by ___________
Ans : friction between the tyres
and the road
SIMPLE HARMONIC
MOTION :
1) Any motion
that repeats itself along the same path in equal intervals of time is called a
_________
Ans : periodic motion
2) Periodic
motion is also called as _______
Ans : harmonic motion
3) A
_____________ is associated with every wave motion.
Ans : simple harmonic motion
4) The time
period of a simple pendulum is ____________
Ans : directly proportional to
the square root of length
ELECTROMAGNETIC
SPECTRUM :
1)What is
Spectrum ?
Ans
: Spectrum is a group of wave lengths or frequencies.
2) When a ray of sun light falls on a prism, the
transmitted light produces a sequence of colours called a _________
Ans : visible spectrum or
VIBGYOR
3) The prisms
made of ______ are used to defect Infra red radiations.
Ans : rock salt
4) The invisible
radiation before violet are called _______
Ultraviolet radiations
5) __________
radiations are characterized by oscillating electric and magnetic fields
perpendicular to each other and perpendicular to the direction of propagation.
Ans : electromagnetic
6) The waves
travelling with velocity of light and consisting of Oscillating electric and
magnetic fields perpendicular to each other and also perpendicular to the
direction of their propagation form the __________
Ans : electromagnetic spectrum
7) The wavelength
of the Visible spectrum extends from about 0.4 µ m to _______ that is from
violet to red colour.
Ans : 0.7 µ m
8) _______________
spectrum is emitted when the excited valence electrons in atoms jump to their
normal states.
Ans : Visible
9) _____________
radiations are emitted by atoms or molecules when they change their states of
rotational to vibrational motion.
Ans : Infra red
10) _______
radiations can be detected by thermopile
Ans : Infra red
11) Infra red
radiations find applications in _________
Ans : physiotherapy
12) Infra red
radiations are also used to take photographs of objects in ________
Ans : darkness
13) The wave
length of the micro waves are in the range from _________ to ________
Ans: 10 µ m to 1 n m
14) Radio waves
have wavelengths from _______ to about
_________
Ans : 1 m ,
100 KM
15) Radio waves
are produced by the electromagnetic oscillators of __________
Ans : low frequency
16) _________
radiations are produced by the high energy transitions of the electrons in
atoms
Ans : Ultra violet
17) We are
protected from ultraviolet radiations of the sun due to _____ layer in our
atmosphere.
Ans: ozone
18) Wave lengths
of x-rays range from ______ to ______
Ans : 0.001 nm,
10nm or 0.01 Å m 100 Å
19) ___________
are produced in discrete wavelengths in individual transitions amon g the inner
electrons of an atom.
Ans : X-rays
20) X-rays of
short wavelengths are also called as __________
Ans : hard x-rays
21) Soft x-rays are used in medical diagnosis called
_____________
Ans : radiography
22) x-rays are
also used to cure some diseases. This
method is called ________
Ans : radio therapy
23) gamma ( γ ) rays are emitted in __________
Ans : radio activity
24) All
electromagnetic waves are ____________ in nature .
Ans : transverse
25) The visible
spectrum is emitted when excited valence ____ in atoms jump to their normal
states.
Ans: electrons
26) The colour of
light emitted by a particular substance is characteristic of the ____ of the
substance.
Ans : atoms
27) The light
emitted from the sun and distant stars give information about the _____ of the
matter present in them.
Ans : composition
28) IR
means_______
Ans : Infra red
29) Infra red
radiations are emitted by _______ when they change their states of rotational
or vibrational motion.
Ans : molecules
30) Hot bodies
form sources of the _______ radiations
Ans : Infra red
31) IR radiations
can be detected by ___________
Ans : Thermopile or bolomometer
32) Microwaves
are produced by high frequency electromagnetic _____ in electric circuits
Ans : Oscillators
33) ___________
waves are used in satellite communications
Ans : Micro waves
34) Mapping of
the radio emissions from extra terrestrial sources is known as ________
Ans : radio radiations
35) UV means
_______
Ans : Ultra violet rays/ ultra
violet spectrum
36) RADAR means
_________
Ans : Radio detection and
ranging
37) The reason of depletion of ozone layer in
atmosphere is due to the reactions with ________
Ans: chloro fluro carbons
38) Speed of
light in vacuum is ___________
Ans : 3 x 10 8 m/sec
39) Microwaves
are often used in _________
Ans : RADAR
40) The type of
radiations used in Radar are ________
Ans : Microwaves
SOUND :
1) Speed of sound
in air is ________
Ans : 333 mps ( in normal
conditions)
2) _____________ is the phenomenon in which if
one of the two bodies of the same
natural frequency is set into vibration, the other body also vibrates with
large amplitude under the influence of the first body.
Ans : Resonance
3) ____________
is not transmitted in stationary waves.
Ans : Energy
4) Sound waves
travel in air are ___________ waves
Ans : longitudinal
5) _____________
waves are formed in a resonating air column.
Ans: Stationary
6) The periodic
vibrations of decreasing amplitude are called ______ vibrations.
Ans : damped
7) Everybody has
its own frequency called ________
Ans : natural frequency
8) Velocity of
sound is maximum in ______
Ans : solids ( like iron rods)
9) The velocity
of sound in vacuum is ________
Ans : zero
10) When the
soldiers cross a suspension bridge they are asked to break their steps to
prevent_______
Ans : resonance
11) A tuning fork
vibrates when a vibrating tuning fork is brought near it. This is due to _____
Ans : rersonance
12) Velocity of
sound on moon is _______
Ans : zero
13) The longest
wave is ________
Ans : Radio wave
14) In a
resonating air column ____ waves are formed.
Ans : stationary
LIGHT
NATURE OF LIGHT & SOURCES OF LIGHT
1) Newton
proposed ________ theory of light
Ans : corpuscles
2) Corpuscles are
_____ by the reflecting surface
Ans : repelled
3) Corpuscles are
______ by the refracting surface
Ans : attracted
4) Wave theory of
light was proposed by __________
Ans : Huygens
5) According to
Newton, the colours of light are due to
difference in the ______ of corpuscles.
Ans : different sizes
6) Light rays can
be produced from __________ body
Ans : luminous
7) Examples of
luminous bodies are _______
Ans: Sun, Stars
8) Maxwell
proposed _________ theory of light
Ans : electromagnetic
9) Light consists
of radiations called ________
Ans : photons
10) Light waves
are ________
Ans : transverse
11) In a ripple
tank , crest of the light wave, behaves as _____ lens
Ans : convex
12) In a ripple
tank the trough of light wave behaves as ______ lens
Ans : concave
13) In a ripple
tank _____ band is formed due to crests
Ans : bright
14) In a ripple
tank _____ band is formed due to troughs
Ans : dark
15) Speed of
light in vacuum is _________
Ans : 3 x 10 8 m/sec
Visual
Photometry:
1) The visual
light is an energy on the _______
Ans : flow
2) Example for
self luminous body is ________
Ans : Sun
3) Unit of
luminous flux is ________
Ans : Lumen
4) Sun light has
its maximum radiant energy close to ________
Ans: green light
LASER:
1)Laser stands for __________
Ans
: Light Amplification by Stimulated Emission of Radiation
2) The light used in destroying ICBM is in itself is __________
Ans
: Laser
3) First laser was called _________
Ans
: pulsed laser
4) The basic scientific principle behind a laser was put
forward by ________
Ans
: Dr. Charles
5) ICBM stands for _____
Ans
: Inter Continental Ballistic Missile
6) The property coherence in Laser is called ________
Ans
: temporal coherence
7) Lack of coherence makes ordinary light an ______
Ans
: optical noise
8) Coherence makes a laser light _____
Ans
: optical music
9) The important characteristic properties of laser are
________
Ans
: 1) coherence 2) directionality
3) monochromacity and high intensity
10) Example for monochromatic light is _______
Ans
: sodium lamp
11) Laser emits light only in one dirction. This is called _____ of laser light.
Ans:
directionality
12) The process of achieving population inversion is
called _________
Ans
: pumping ( It is a word used in Lasers)
13) The process of electrons being released on their own
from the excited states in atoms and emitting incoherent light is called
________
Ans
: spontaneous emission
14) _______ are used for bloodless surgery
Ans
: Lasers
15) Lasers are used now for __________
Ans
: drilling, cutting materials
16) Lasers are used in guided ______ and to deflect enemy
target
Ans
: missiles
17) Lasers employed in special 3-dimensional photography
are called _______
Ans
: Holography
18) The development of lasers which helped in
establishing a new revolutionary method of communications called __________
Ans
: fibre optic communication
19) The spread of wavelength about the maximum intensity
is called ______
Ans
: Band width
20) Ruby laser is an example for ______
Ans
: solid laser
21) Helium – Neon laser is an example for _______
Ans
: gaseous laser
22) The three dimensional photography is called _____
Ans
: Holography
23) The process of achieving “population inversion” is
called_____
Ans
: pumping
24) By ______ large energy can be concentrated into an
extremely small band width.
Ans
: Monochromacity
25) The light from an ordinary light source spreads out
uniformly in all directions and forms ______ wave fronts around it.
Ans
: spherical
