Unit 1: Light
Ans:
Q. The image formed by a concave mirror is virtual, erect and larger than the size of object. What is the position of an object and where the image is formed?
Ans: The position of the Object is between the Pole and Principle Focus of the mirror.
The Image will be formed behind the mirror.
Q. Define principal focus of a concave mirror.
Ans: The principal focus of a concave mirror is a point on principal axis at which all the light rays parallel to it meet after reflection.
Q. The image formed by concave mirror is Real, Inverted and Larger than object. What is the position of the object?
Ans: In a concave mirror, when object is placed between focus and curvature of center, the image formed is real, inverted and larger than the object.
Q. Define centre of Curvature of a spherical mirror?
Ans: Centre of curvature of a spherical mirror is defined as the centre of the sphere of which the mirror is a part of.
In other words, it is the centre of the sphere from which the spherical mirror is sliced.
Q. A concave lens is also a diverging lens. Why?
Ans: Concave lens is also called diverging lens because it diverges all the rays of light away from its principal axis.
Q. Define principal axis of a spherical mirror.
Ans: Principal axis is the line passing through the pole, centre of curvature and focus of a spherical mirror.
Q. For what position of an object, a concave mirror forms a real image equal in size of object.
Ans: When the object is placed at Centre of Curvature of a concave mirror, The image formed is real and equal in size of object.
Q. Give any one condition when no refraction takes place.
Ans: The refraction will not take place under two conditions:
I. The refractive index of two mediums is equal.
II. The Angle of Incidence is 0.
Ans: Refraction is caused when the rays of light travels from rearer to denser medium or vice versa.
Q. Convex lens is also called converging lens. Why?
Ans: Convex lens is also called converging lens because it converges all the rays of light towards its focus.
1. Water 2. Glass 3. Plastic 4. Clay
Ans: Clay
1. Between Principal focus and centre of Curvature
2. At centre of curvature
3. Beyond Centre of curvature
4. Between Pole and principal focus
Ans: Between Pole and Principal focus
Q. Where should a object be placed infront of convex lens to get real image of size of object?
1. At principal focus
2. Twice the focal length
3. At infinite
4. Between optical centre and principal focus
Ans: Twice the focal length of lens.
1. Concave
2. Convex
3. Mirror is concave, Lens is convex
4. Mirror is convex, Lens is concave
Ans: Concave
Q. No matter how far you stand from a mirror, your image appears erect. The mirror is likely to be:
1. Plane only
2. Concave only
3. Convex only
4. Either Plane or convex
Ans: Either plane or Convex.
Q. Which of following lenses would you prefer to use while reading small letters in a dictionary?
1. A concave lens of focal length 50 cm
2. A convex lens of focal length 50 cm
3. A convex lens of focal length 5 cm
4. A concave lens of focal length 5 cm
Ans:
A convex lens of focal length 5 cm
1. Zero 2. Infinity 3. Finite 4. None
Ans: Infinity.
Q. Which mirror is used in headlight of car
Ans: Concave mirror
Ans: Concave mirror.
Q. Which mirror is used as side and rear view mirror?
Ans: Convex mirror
Ans: Concave mirror.
Ans: Concave mirror.
Q. The refractive index of diamond is 2.42. What is the meaning of this statement?
Ans: It means light travels 2.42 times slower in diamond.
Ans: When focal length of lens is 1 meter, Its power is 1 dioptre.
Q. Object AB is placed at centre of Curvature of a concave mirror. The inverted image of the object will be formed at centre of curvature. Draw a ray diagram of it.
Ans:
Ans:
Refractive index of water is 1.33
Refreactive index of crown glass is 1.52
Q. A ray
of light goes from water into air. Will it bend towards normal?
Ans: No,
the ray of light will bend away from the normal.
Q. Name
the mirror which can give an erect and enlarged image of an object.
Ans: The
Concave mirror can give erect and enlarged image of an object when it is placed
between Focus and Pole.
Q. Which
type of lens has positive power?
Ans: Convex
lens has positive power as its focus lies towards the right side of lens.
Q. A
diverging lens has a focal length of 0.10 m. What is its Power?
Ans: Power
of Lens= 1/Focal length.
= 1/-0.10
= - 100/10
= - 10
Q. The
power of lens is + 2.5 D, what kind of lens it is and what is its focal length?
Ans:
Since the power of lens is +, the lens should be Convex.
Its focal
length will be given as
1/F = 2.5
F
= 1/ 2.5
F = 0.40 m
Q. A
concave lens produces an image 20 cm from the lens of an object placed 30 cm
from the lens. Find the focal length of the lens.
Ans:
Here, V = - 20 , U = -30
We have,
1/V – 1/U
= 1/F
1/-20 –
1/-30 = 1/F
1/-20 +
1/30 = 1/F
-3 +
2 = 1/F
60
-1/60 = 1/F
F = -
60
Q. Which
type of mirror could be used as a shaving mirror?
Ans: The
Concave mirror is used as a shaving mirror as it produces enlarged and erect
image when the object is between Focus and Pole.
Q. Name
the phenomenon due to which swimming pool appears less deep that it really is.
Ans: The
Swimming pool appears less deep due to the phenomenon of Refraction.
Q. Which
type of lens are thinner in the middle than at the edges?
Ans:
Concave Lens are thinner in the middle than the edges.
Q. Name
the mirror which gives an erect and diminished image of an object.
Ans: Convex
mirror gives erect and diminished image of an object.
Q. A ray
of light passes from air to glass, Is the angle of refraction greater or less
than angle of Incidence?
Ans: When a
ray of light passes from air to the glass, it will bend towards the normal.
Hence, the angle of refraction is less than the angle of Incidence.
Q. Which
type of lens is thicker in middle than at the edges?
Ans: Convex lens is thick in the middle than at the edges.
Q. The image formed by a concave mirror is observed to be virtual, erect and larger than the object. Where should be the position of the Object?
Ans: The object should be placed between Pole (P) and Focus (F) of the concave mirror.
Q. There is a Spherical mirror having the radius of curvature of 20 cm. What is its focal length?
Ans: The focal length is half of the radius of curvature. Therefore, Radius of curvature will be 10 cm.
Q. Absolute refractive index of Kerosene, turpentine and water are 1.44, 1.47 and 1.33 respectively. In which of these does light travel fastest?
Ans: The speed of light is inversely proportional to the refractive index. Therefore, the light travels fastest in water which has lowest refractive index of three.
Q. A ray of light traveling in air enters obliquely into water. Does the light ray bend towards the normal or away from the normal?
Ans: Since the ray of light is travelling from rarer to denser medium. Therefore, it will bend towards the normal.
Q. The focal length of a plane mirror is:
a) 0 b)
infinite c) 25 cm d) -25 cm
Ans: b) Infinite
Q. When the object is placed beyond centre of curvature of a concave mirror, the image formed will be:
a. Erect and Dim b. Erect and Magnified c. Inverted and Dim d. Inverted and Magnified
Ans: c. Inverted and Dim
Q. The image formed by a concave mirror is observed to be virtual, erect and magnified. Where should be the position of the object?
Ans: The object shall be placed between the Pole and the Focus of the concave mirror.
Q. A spherical mirror and a thin spherical lens have each a focal length of – 15 cm. The mirror and the lens are likely to be:
a. Both Concave b. Both Convex
c. The mirror is concave and the lens is convex
d. The mirror is convex and the lens is concave
Ans: c. The mirror is concave and the lens is convex
Q. If you are not able to read small letters in a dictionary, which of the following lenses would you prefer to use?
a. Concave lens of focal length 50 cm b. Concave lens of focal length 50 cm
c. Convex lens of focal length 5 cm d. A concave lens of focal length 5 cm
Ans: c. Convex lens of focal length 5 cm
Q. Where should an object be placed Infront of a convex lens to get a real image of the size of the object?
Ans: The object should be placed at the principal focus (2F1) of the convex lens
Q. The focal length of a concave lens is 100 cm. Calculate its power in Dioptres:
a. 1 D b. 0.5 D c. 2 D d. 0.2 D
Ans: a. 1 D
Q. No matter how far you stand from the mirror, your image appears erect. The mirror is likely to be:
a. Plane b. Concave c. Convex d. Either Plane or Convex
Ans: d. Either Plane or Convex
Q. The power of concave lens is 0.5 D. Its focal length will be:
a. 100 cm b. 200 cm c. 150 cm d. 250 cm
Ans: b. 200 cm
Unit 2: Human Eye and Colourful World
Q. Which natural phenomenan among the following takes place because of scattering of light?
A. Blue colour of sky
B. Twinkling of stars
C. Advanced sunrise and delayed sunset
D. Both B and C
Ans: A. Blue colour of sky
Ans: In sunlight the size of the pupil gets small. When we enter dark room, the light entering through small pupil is very less. It takes some time for pupil to adjust.
Q. What is Dispersion?
Ans: Dispersion is the separation of white light into its constituent colours in form of VIBGYOR.
Q. A student has difficulty reading blackboard while sitting in last row. What could be the defect the child is suffering from? How could it be corrected?
Ans: The child is suffering from myopia.
It can be corrected by concave lens.
1. Presbyopia 2. Accomodation
3. Near sightedness 4. Far sightedness
Ans:
Accomodation
1. Cornea 2. Iris 3. Pupil 4. Retina
Ans: Retina
Q. The least distance of distinct vision for adult is about:
1. 25 m 2. 2.5 cm 3. 25 cm 4. 2.5 m
Ans: 25 cm
1. Pupil 2. Retina 3. Ciliary muscles 4. Iris
Ans: Ciliary muscles
Ans: Yellow spot
Ans: Black spot
1. Lens 2. Iris 3. Cornea 4. Pupil
Ans : Lens
Q. Human eye forms image of object at
1. Cornea 2. Retina 3. Pupil 4. Iris
Ans: Retina
Q. Which defect of eye cannot be corrected by spectacles.
1. Myopia 2. Presbyopia 3. Cataract 4. Hypermetropia
Ans: Cataract
Q. A person is wearing spectacles of concave lens of suitable focal length. What kind of defect of vision is he having?
A. Myopia
B. Hypermetropia
C. Presbiopia
D. Both B & C
Ans: A. Myopia
A. Advanced sunrise and delayed sunset
B. Twinkling of stars
C. Blue colour of sky
D. Both A and B
Ans: D: Both A and B
Q. Formation of rainbow is an example of
A. Atmospheric refraction
B. Scattering of light
C. Dispersion of light
D. Both A and B
Ans: D. Both A and B
Q. The colored
light having maximum speed in the glass prism is:
A.
Blue B. Green C. Violet D. Yellow
Ans: Yellow
Q Which of
the following color of white light has the least wave length?
a. Red b. Orange
c. Violet d. Blue
ans: c.
Violet
Q. There
are two types of light sensitive cells in the human eye:
i. Where
are they found? ii. What is each
type called?
Ans: The
two types of light sensitive cells in human eye are found inside the Retina.
ii. They
are called as Rod cells and Cone cells.
Q. Make
two diagrams to explain refraction and dispersion
Ans:
Q. Why
do stars seem higher than they actually are?
Ans: The
stars seem higher than they actually are is due to atmospheric refraction.
Q. Why
do stars twinkle in a clear night?
Ans: The stars
twinkle in a clear night due to atmospheric refraction.
Q. What
is atmospheric refraction? Give its causes.
Ans: Atmospheric
refraction is defined as the refraction of light caused by the earth's
atmosphere. Atmospheric Refraction occurs because the different layers of
earth's atmosphere vary in terms of optical densities.
Q. A
beam of white light falling on the glass prism cannot be:
a.
Deviated b. Dispersed c. Focused
d. Refracted
Ans: c. Focused
Q. At the time of sunset and sunrise, the sun and the surrounding sky appear red. This red colour of the sun and the sky is because:
A. Red colour is least scattered B. Blue colour is least scattered
C. Red Colour is most scattered D. All colours are equally Scattered
Ans: A. Red colour is least scattered
Q. A student has difficulty in reading blackboard while sitting in the last row. What could be the defect the child is suffering from? How can it be corrected?
Ans: Since the child cannot see the blackboard clearly, she/he is suffering from 'myopia' or 'short - sightedness'.
Q. Assertion: When a compass needle is moved away from a current carrying straight conductor, the deflection of the needle decreases
Reason: The strength of magnetic field decreases on moving away from the conductor
A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true and R is not the correct explanation of A
C. A is True, R is False
D. A is False, R is True
Ans: A. Both A and R are true and R is the correct explanation of A
Q. The danger signals installed at the top of building are red in colour. These can be easily seen from a distance because among all the colours, the red light:
a. Is scattered the most by the smoke or fog b. Is scattered the least by the fog
c. Is absorbed the most by the fog d. Moves fastest in the air
Ans: b. Is scattered the least by the fog
Q. Which of the following statements is correct?
a. A person with myopia can see distant objects clearly
b. A person with hypermetropia can see nearby objects clearly
c. A person with myopia can see nearby objects clearly
d. A person with hypermetropia cannot see distant objects clearly
Ans: c. A person with myopia can see nearby objects clearly
Q. A person cannot see distant objects kept beyond 2 m. This defect can be corrected by using a lens of power:
a. +0.5D b. -0.5D c. +0.2D d. -0.2D
Ans: b. -0.5D
Hint: The person is suffering from Myopia and hence needs a concave lens of power -0.5 D to correct the problem.
Q. Which of the following statements is correct regarding the propagation of light of different colours of white light in air?
A. Red light moves fastest
b. Blue light moves faster than green light
c. Yellow light moves with the mean speed as that of the red and the violet light
d. All the colours of the white light move with the same speed
Ans: d. All the colours of the white light move with the same speed
Hint: All colours move at the same speed in the vacuum and air but in much denser medium, different colours move at different speeds.
Unit 3: Electricity
Ans: If the resistance is doubled then current in the circuit become half.
Ans: Copper is used in electric fitting because it is good conductive, highly ductile and inexpensive.
Q. Give the quantitative definition of electric current.
Ans: Quantitatively, Electic current is the rate of flow of electric charge (Q) through a conductor per unit time (t).
Current = Q/t
A. 1/25 B. 1/5 C. 5 D. 25
Ans: D. 25
Q. Which of following terms does not represent electric power in circuit?
A. I2R B. IR2 C. VI D. V2/R
Ans: IR2
A. 100 w b. 75 w c. 50 w d. 25 w
Ans: 25 w
Q. Two conducting wires of same material and of equal lengths and equal diameters are first connected in series and then in parallel in an electric circuit. The ratio of heat produced in series and parallel combination would be
A. 1:2 b. 2:1 c. 1:4 d. 4:1
Ans: C. 1:4
Ans: In parallel
Q. What is SI unit of conductance
Ans: Seimen
Ans: Alloy of tin and lead
Ans: Tungesten
Ans: Nichrome
Q. In electric fittings we mostly use copper wires? Why
Ans: Because copper is good conductor of electricity.
Q. At
the time of short circuit, what happens to the current?
Ans: At the
time of short circuit, the current increases multifold. It may cause fire.
Q. The
heating elements of electrical heating devices are usually made of:
a.
Tungsten b. Bronze c. Nichrome d. Argon
Ans: c.
Nichrome
Q. Which
of the following characteristics is not suitable for a fuse wire?
a. Thin and
Short b. Thick and short c. Low melting point d. Higher resistance
Ans: b.
Thick and Short
Q. The
heat produced by passing an electric current through fixed resistor is
proportional to the square of :
a.
Resistance b. Current c. Temperature d. Time
Ans: b. Current
Q. If
the current flowing through a fixed resistor is halved, the heat produced in it
will become:
a. Double b. One half c. One fourth d. Four times
Ans: c. One fourth
Q. An
electric fuse works on the:
A. Chemical
effects of current B. Magnetic
effects of current
C. Lighting
effect of current D. Heating
effect of current
Ans: D. Heating effect of Current
Q. Find
the energy transferred by a 100 W electric bulb in 1 minute.
Ans: We
have,
Energy
= Power x Time
Energy = 100 w x 60 s
Energy = 6000 Joules
Q. Of
which substance is the fuse wire made?
Ans: Fuse
wires are made of Nichrome.
Q. In household
circuits, is a fuse wire connected in series or in parallel?
Ans: The
fuse wire is connected in series in a household circuit.
Q. There is a conductor having the resistivity P. If the conductor is stretched to double of its length, what will be its new resistivity?
Ans: Resistivity does not depend on the length of the conductor. Hence, doubling the length will not change its resistivity.
Q. Electrical resistivity of a given metallic wire depends
upon:
a) its length b) its thickness c) its shape d) nature of material
Q. The device used to measure electric current is called
a) Generator b) Ammeter c) Galvanometer d) Motor
Q. A wire of resistance 1 ohm is divided into two halves and both halves are connected in parallel. The new resistance will be:
a. 1 ohm b. 2 ohm c. 0.5 ohm d. 0.25 ohm
Ans: d. 0.25 ohm
Q. The energy given to each coulomb of charge passing through a 6V battery is :
a. 12J b. 6J c. 3J d. 18J
Ans: b. 6J
Q. Three resistors having resistances of 2 ohm, 4 ohm and 8 ohm are connected in Parallel. Their equivalent resistance will be:
a. 10 ohm b. 14 ohm c. 8/7 ohm d. Between 2 ohm and 8 ohm
Ans: c. 8/7 ohm
Unit 4: Magnetic effect of electric current
A. Mass B. Speed C. Velocity D. Momentum
Ans: Velocity and momentum
A. South B. East
C. Downwards D. Upwards
Ans:
D. Upwards
Ans: When current carrying coil is placed in magnetic field, It feels torque which rotate the coil.
Ans: The split ring reverse direction of current after half cycle.
Ans: Cell, Battery, D.C Generator.
Ans: A.C generators.
A. Two revolutions B. One Revolution
C. Half Revolution D. One fourth revolution
Ans: Half Revolution.
a. Straight lines
b. Radial lines
c. Concentric circle centred on wire
Ans: c. Concentric circle centred on wire
Q. The phenomenon of electro magnetic induction is:
A. Process of charging a body
B. Process of generating magnetic field
C. Producing induced current in a coil
D. Process of rotating coil of motor
Ans: C. Producing induced current in a coil.
A. Generator B. Galvanometer
C. Ammeter D. Motor
Ans: a. Generator
A. D.C generator has higher voltage
B. A.C generator has higher voltage
C. AC generator has slip rings while DC generator has commutator
Ans: AC generator has slip rings while DC generator has commutator
A. Reduces B. No change C. Increases heavily D. Vary
Ans: C. Increases heavily
A. Galvanometer B. Transformer
C. X rays D. Voltmeter
Ans: B. Transformer
A. Electric field
B. Magnetic field
C. Both electric and magnetic field
Ans: C. Both electric and magnetic field
Q. When coil is kept stationary relative to magnetic, the galvanometer gives deflection:
A. Maximum B. Zero C. Constant
Ans: Zero
I. Amperes swimming rule
II. Fleming's right hand thumb rule
III. Fleming's left hand thumb rule
IV. Faradays rule
Ans: II. Fleming's right hand thumb rule.
Q. Magnitude of magnetic field around a current carrying conductor at any point is:
I. Directly proportional to intensity of electric current
II. Inversely proportional to the distance of conductor
III. Directly proportional to the distance of conductor
IV. Both A & B
Ans: Both A & B
Q. To find the direction of deflection of compass needle due to magnetic field of current carrying conductor, we use
I. Amperes swimming rule
II. Fleming's right hand thumb rule
III. Fleming's left hand thumb rule
IV. Faradays rule
Ans: I. Amperes swimming rule
Q. Current carrying conductor is a
I. Permenant magnet
II. Temporary magnet
III. Natural magnet
IV. None of these
Ans: II. Temporary magnet
Q. Which among the following produces strong magnetic field?
I. Permenant magnet
II. Natural magnet
III. Bar magnet
IV. Electromagnet
Ans: IV: Electromagnet
A. The field consists of straight lines perpendicular to the wire
B. The field consists of straight lines parallel to the wire
C.The field consists of radial lines originating from the wire
D.The field consists of concentric circles centred on the wire
Ans: D.The field consists of concentric circles centred on the wire
Q . The phenomenon of electromagnetic induction is
A. the process of charging a body
B. the process of generating magnetic field due to a current passing through a coil
C. producing induced current in a coil due to relative motion between a magnet and the coil
D. the process of rotating a coil of an electric motor
Ans: C. producing induced current in a coil due to relative motion between a magnet and the coil
Q. The device used for producing electric current is called a
A. generator
B. galvanometer
C. ammeter
D. motor
Ans: A. generator
Q. The essential difference between an AC generator and a DC generator is that
A. AC generator has an electromagnet while a DC generator has permanent magnet.
B. DC generator will generate a higher voltage.
C. AC generator will generate a higher voltage.
D. AC generator has slip rings while the DC generator has a commutator.
Ans: D. AC generator has slip rings while the DC generator has a commutator.
Q. At the time of short circuit, the current in the circuit
A. reduces substantially
B. does not change
C. increases heavily
D. vary continuously
Ans: C. Increases heavily
Q. State
Fleming’s left-hand rule.
Ans: Fleming's
left-hand rule is used to find the direction of the force acting on the
current carrying conductor placed in a magnetic field.
It states
that if we arrange our thumb, forefinger and middle finger of the right-hand
perpendicular to each other, then the thumb points towards the direction of the
motion of the conductor relative to the magnetic field, the forefinger points
towards the direction of the magnetic field and the middle finger points
towards the direction of the induced current.
Q. Out
of A.C generator and a D.C generator, which one uses a commutator?
Ans: An D.C
generator uses commutator.
Q. Out
of A.C generator and a D.C generator,
which one uses slip rings?
Ans: An A.C
generator uses Slip rings.
Q. What
is magnetic field? State any two properties of magnetic field lines?
Ans: The
magnetic field is a vector field that describes magnetic influence of the
charges and magnetic materials.
Two
properties of magnetic field lines are:
1. They
never cross each other.
2. They
flow from North to south pole outside the magnet.
Q. What
type of generator is used at power stations?
Ans: A.C
generator is used in power stations.
Q. What
is the principle of electric motor? Name two devices in which electric motor is
used?
Ans: Electric motor works on the principle of Flemings Left hand rule.
Electric motors are used in water pumps, electric fans, electric mixers etc.
A. The field consists of straight lines perpendicular to the wire
B. The field consists of straight lines parallel to the wire
C. The field consists of concentric circles centred on the wire
D. Both A and B
Ans: C. The field consists of concentric circles centred on the wire
Q. Every current carrying conductor produces magnetic field, this phenomenon was discovered by:
A. Maxwell B. Oersted C. Faraday D. Coulomb
Ans: Oersted
Q. The direction of magnetic field around a current carrying straight conductor can be determined by:
A. Flemings right hand rule B. Flemings left hand rule
C. Faradays Rule D. Right hand thumb rule
Ans: Flemings right hand rule
Q. The magnitude of magnetic field produced by a current carrying straight conductor is:
A. Directly proportional to the Intensity of current
B. Directly proportional to the distance from conductor
C. Inversely proportional to distance from the conductor
D. Both A and C
Ans: D. Both A and C
Q. If the direction of electric current in a current carrying conductor is upwards, the direction of magnetic field lines will be:
A. Clock wise B. Anticlockwise C. Both A and B D. Can’t be determined
Ans: B. Anticlockwise
Assertion (A): Magnetic field lines don't intersect each other
Reason (R): Magnetic field lines are imaginary lines, the tangents to which any point gives the direction of the field at that point.
A and R are true and R is correct explanation of A
Both A and Rare true and R is not correct explanation of A
A is true but R is false
A is false but R is true
Q. Magnitude of a magnetic field around a current carrying conductor at any point is:
a. Directly proportional to the intensity of electric current
b. Inversely proportional to the distance from the conductor
c. Directly proportional to the distance from the conductor
d. Both A and B
Ans: d. Both A and B
Q. Assertion: When a current carrying conductor is placed in a magnetic field, It experiences a force
Reason: The force acting on a current carrying conductor is only due to the external magnetic field.
A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true and R is not the correct explanation of A
C. A is True, R is False
D. A is False, R is True
Ans: C. A is True, R is False
Hint: The force acting on the conductor is due to the interaction of external magnetic field and the magnetic field produced due to the current flowing in the conductor
Q. Assertion: When a compass needle is moved away from a current carrying straight conductor, the deflection of the needle decreases
Reason: The strength of magnetic field decreases on moving away from the conductor
A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true and R is not the correct explanation of A
C. A is True, R is False
D. A is False, R is True
Ans: A. Both A and R are true and R is the correct explanation of A
Q. Assertion: When the direction of current in a current carrying straight conductor is upwards, the direction of magnetic field lines is clockwise
Reason: To find the direction of magnetic field lines, we use maxwells right hand thumb rule
A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true and R is not the correct explanation of A
C. A is True, R is False
D. A is False, R is True
Ans: D. A is False, R is True
Q. To find out the direction of deflection of the compass needle due to magnetic field of a current carrying conductor, we use:
a. Amperes swimming rule b. Flemings right hand rule
c. Maxwells Rule d. Flemings left hand rule
Ans: a. Amperes swimming rule
Q. Which among the following is used to find the direction of magnetic field lines around a current carrying straight conductor ?
a. Amperes swimming rule b. Flemings right hand rule
c. Maxwells right hand thumb rule d. Flemings left hand rule
Ans: c. Maxwells right hand thumb rule
Unit 5: Sources of Energy
A. Sunny day B. Cloudy day C. Hot day
D. Windy
Ans: B. Cloudy day
A. Wood B. Gober C. Atomic energy D. Coal
Ans: C. Atomic energy
Q. Which of following is not ultimately derived from sun's energy?
A. Geothermal energy B. Wind energy
C. Nuclear energy D. Biomass
Ans:
C. Nuclear energy
A. CNG B. LPG C. Oxygen D. Hydrogen
Ans: C. Oxygen
A. Methane B. Ethane C. Propane D. Pentane
Ans: Pentane
A. Coal B. Biogas
C. Atomic energy D. Cowdung
Ans: Atomic energy.
