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In the context of Faraday's law, what does the negative sign in the equation signify?
A) It indicates a positive change in flux
B) It indicates a negative change in flux
C) It signifies the direction of the induced EMF
D) It signifies the direction of the magnetic field - ANSWER-C) It signifies the direction of
the induced EMF
What is the purpose of a transformer in an electrical circuit?
A) To convert electric energy into work
B) To change the direction of current flow
C) To change the voltage in a circuit
D) To increase the resistance of the circuit - ANSWER-C) To change the voltage in a
circuit
According to Faraday's law, what induces an EMF in a generator?
A) Change in the magnetic field strength
B) Change in the loop area
C) Change in the angle between the loop and the magnetic field
D) Change in the number of loops - ANSWER-C) Change in the angle between the loop
and the magnetic field
What does Ampere's circuit law describe?
A) The behavior of electric field lines
B) The behavior of magnetic field lines
C) How magnetic fields are created by moving charges or changing electric fields
D) The relationship between electric and magnetic flux - ANSWER-C) How magnetic
fields are created by moving charges or changing electric fields
How are electric and magnetic waves related according to Maxwell's equations?
A) They are always in phase with each other
B) They are always out of phase with each other
C) They are unrelated phenomena
, D) They occur together and travel perpendicular to each other - ANSWER-D) They
occur together and travel perpendicular to each other
What is the relationship between the speed of an electromagnetic wave and the
amplitude of the electric and magnetic fields?
A) Speed is directly proportional to the amplitude of the electric field
B) Speed is inversely proportional to the amplitude of the electric field
C) Speed is directly proportional to the amplitude of the magnetic field
D) Speed is inversely proportional to the amplitude of the magnetic field - ANSWER-A)
Speed is directly proportional to the amplitude of the electric field
What is the relationship between the energy of an electromagnetic wave and the
amplitude of its electric or magnetic field?
A) The energy is directly proportional to the amplitude
B) The energy is inversely proportional to the amplitude
C) The energy is proportional to the square of the amplitude
D) The energy is unrelated to the amplitude - ANSWER-C) The energy is proportional to
the square of the amplitude
What are the SI units of intensity?
A) Newtons per meter squared
B) Joules per meter squared
C) Watts per meter squared
D) Hertz per meter squared - ANSWER-C) Watts per meter squared
What determines the critical angle for total internal reflection?
A) The speed of light in the incident material
B) The speed of light in the refracted material
C) The angle of incidence
D) The angle of refraction - ANSWER-B) The speed of light in the refracted material
For a double concave lens, where is the image located relative to the lens?
A) On the opposite side of the object
B) On the same side of the object
C) In front of the object
D) Behind the object - ANSWER-B) On the same side of the object
What is the characteristic of the focal point for concave mirrors?
A) Real
B) Virtual