The colour or an opaque object is due to the colour it
absorbs
refracts
reflects
scatters
Correct Answer :
C. reflects
Related Questions
Who discovered that the Cree Call acceleration Is the same for any object at a given place?
Newton
Pascal
Archimedes
Galileo
Heat transfer
cools the body that transfers it
heats the body that absorbs the heat
may change the physical state of the substance
All the above
When an electric apparatus is fitted with a three core flexible lead the insulation on the three wires is distinctively coloured. The present international convention is
brown for earth, yellow for live, light blue for neutral
green for earth, yellow for live, brown for neutral
yellow for earth, green for live, brown for neutral
brown or red for live, light blue or black for neutral and green or yellow for earth
Which of the following is known as freon?
Liquid ammonia
Carbon tetrafluoride
Dichloro-difluoro-methane
Sulphur dioxide
On the Kelvin scale, the melting point of ice is
0 K
273 K
373 K
100 K
Skating on ice is possible because
the surface of ice is smooth
ice is cold
the pressure on the ice due to skate melts the ice by lowering its melting point forming a thin film of water
the pressure on the ice due to skate raises its melting point
The cover of a solar cooker is made of glass because
it absorbs sun's rays
it reflects sun's rays
it retains the heat inside by the greenhouse effect
it radiates heat better than metals
Acoustics is a property or
Physics
Chemistry
Biology
Economic
In the fuse of an electrical installation blows out
replace the fuse by a thin wire
replace the fuse by a thick copper wire
replace the fuse by a fuse wire of proper rating
replace the fuse by nichrome wire
The tiniest of the stars belong to the group known as
Giant stars
White Dwarf stars
Neutron stars
Super-giant stars
The function of a ruse wire is
to stabilise the voltage
to decrease the current supply
to increase the current supply
to prevent an unduly high current from passing through a circuit
An ammeter has
a high resistance
a very low resistance
no resistance at all
resistance of 400 ? w
The atmosphere gets heated up mainly by
direct sun's rays
radiation from earth's surface
radiogenic heat (resulting from radioactive decay)
cosmic rays coming from space
A boat loaded with rocks floats in the middle of a swimming pool. A man in the boat throws the rocks overboard. The level of water in the pool will
increase
decrease
remain the same
first decrease and then increase
Out of the following which element has the longest half-life period?
Radium
Radon
Uranium-238
Plutonium
The unit of heat energy is
watt
degree
joule
erg
A projectile is fired at an angle with the horizontal with a small velocity. Its horizontal range will be maximum when the angle with the horizontal is
0°
30°
45°
60°
The velocity of sound in a medium is
directly proportional to its pressure
inversely proportional to the square root of its pressure
directly proportional to the square root of its pressure
independent of its pressure
When are temperature resistance
increases
decreases
remains the same
first increases then decreases
A solid ball of metal has a spherical cavity inside it. When the ball is heated the volume of the cavity will
increase
decrease
remain unaffected
have its shape changed
The radiator in a car serves to
cool the engine
heat up the engine
start the car
moderate the speed
Photoelectric cell is a device which converts
light energy into electrical energy
electrical energy into light energy
magnetic energy into electrical energy
electrical energy into mechanical energy
Raindrops assume a spherical shape because or
adhesion
surface tension
gravitational force
atmospheric pressure from all sides
The acoustical quality of a room depends on
the size and shape of the room
the ability of the ceiling, walls and floor to exclude unwanted sound
the use of furnishings made of sound absorbing materials
All the above
The filament used in the electric lamp is made of
nichrome
tungsten
copper
aluminium
The colour or an opaque object is due to the colour it
absorbs
refracts
reflects
scatters
The instrument used to determine the RD (Relative Density) of a liquid by the principle of floatation is
Hygrometer
Hypsometer
Hydrometer
Densimeter
A boy is swinging a ball attached to a string in a horizontal circle. If the string snaps
the ball will travel towards the centre of the circle and fall down
it will continue to travel along a tangent to the circle at the point the ball was at the time of snapping and finally fall down
it will fall down at the same place where the string breaks
None of these
The inability of a body to change its state of rest or uniform motion along a straight line is called its
momentum
velocity
acceleration
inertia
Body A is kept in contact with body B. Heat will flow from A to B if
the heat content of A is greater than that of B
the temperature of A is greater than that of B
the specific heat of A is greater than that of B
the specific heat of B is greater than that of A