Electricity

Total Questions: 50

31. What is the unit of the physical quantity "Inductance"? [S.S.C. Online CHSL (T-I) 2.02.2017 (Shift-I)]

Correct Answer: (c) Henry
Solution:

The unit of the physical quantity "Inductance" in the International System of Units (SI) is the henry, with the symbol H.

One henry is defined as the inductance that produces a voltage of one volt when the current through it changes at a rate of one ampere per second. 

Mathematically, this can be expressed as:

Where:

  • is the induced voltage in volts (V) 
  • is the inductance in henries (H)
  • is the rate of change of current in amperes per second (A/s)

32. Who Invented Induction Coil? [S.S.C. Online CHSL (T-1) 2.02.2017 (Shih-I)]

Correct Answer: (d) Nicholas Callan
Solution:An induction coil is a device that receives high voltage from a low-voltage source.
  • It was discovered by Nicholas Callen in 1836.
  • It consists of two coils wrapped on a core, which are called the primary and secondary coils.
  • Vehicles have ignition coil on the principle of the induction coil.

33. The term 'Higgs Boson' is associated with- . [S.S.C. Online Graduation Level (T-1) 3.09.2016 (Shift-I)]

Correct Answer: (c) God Particle
Solution:The Higgs boson is a fundamental particle that was first hypothesized in the year 1964 and its experimental verification was done on March 14, 2013.
  • Outside the scientific community and by the media, this article is referred to as the God Particle.
  • Britain's Peter Higgs and Belgium's François Englert were awarded the 2013 Nobel Prize in Physics for the discovery of the Higgs boson particle.

34. In physics, the particles called 'Higgs Boson' are also known as: [S.S.C. JE Civil Exam 30.10.2020 (Shift-I)]

Correct Answer: (c) God particle
Solution:The Higgs boson is a fundamental particle that was first hypothesized in the year 1964 and its experimental verification was done on March 14, 2013.
  • Outside the scientific community and by the media, this article is referred to as the God Particle.
  • Britain's Peter Higgs and Belgium's François Englert were awarded the 2013 Nobel Prize in Physics for the discovery of the Higgs boson particle.

35. If electric resistance is to be decreased, then the number of resistances should be connected in- [S.S.C. Online Graduation Level (T-1) 31.08.2016 (Shift-II)]

Correct Answer: (b) Parallel
Solution:If the resistors are connected in such a way that the potential difference across each resistance remains the same, then it is a parallel series connection of resistors.
  • This adjustment is used in domestic electrical wiring installation to obtain minimum resistance.

36. What is the name of the phenomena in Physics and astronomy that involves the splitting of a spectral line into two or more components of slightly different frequencies when the light source is placed in a magnetic field? [S.S.C. Online Graduation Level (T-1) 4.03.2020 (Shift-III)]

Correct Answer: (a) Zeeman Effect
Solution:The Zeeman effect is named after the Dutch physicist Peter Zeeman.
  1. It refers to the effect in which a spectral line obtained from a light source is split into parts due to the presence of a magnetic field.
  2. The Zeeman effect is a valuable tool in both physics and astronomy:
  • Physics: It helps in understanding the energy levels and magnetic properties of atoms.
  • Astronomy: It is used to measure the magnetic fields of stars, including our Sun, and other celestial objects. The splitting pattern of spectral lines observed from these objects can reveal the strength and structure of their magnetic fields.

37. A_______is a passive two terminal electrical component that implements electrical resistance as a circuit element. [S.S.C. JE Mechanical Exam 22.03.2021 (Shift-I)]

Correct Answer: (d) Resistor
Solution:

A resistor is a passive two-terminal electrical component that implements electrical resistance as a circuit element.

Key Characteristics of a Resistor:

  • Passive Component: It doesn't generate its own energy but rather dissipates electrical energy in the form of heat.
  • Two-Terminal: It has two points of connection in a circuit.
  • Electrical Resistance: Its primary function is to oppose the flow of electric current. The amount of opposition is quantified by its resistance value, measured in ohms ().

38. _______states that the total current entering a junction equals to the total current leaving the junction. [S.S.C. Online CHSL (T-I) 22.01.2017 (Shift-III)]

Correct Answer: (d) Kirchhoff's First Law
Solution:

The statement "the total current entering a junction equals the total current leaving the junction" is known as Kirchhoff's Current Law (KCL).

Kirchhoff’s Current Law (KCL)

  • Definition:
    At any electrical junction (or node) in a circuit, the sum of currents flowing into the junction is exactly equal to the sum of currents flowing out of the junction.

  • Mathematically:

    ∑Iin=∑Iout\sum I_{\text{in}} = \sum I_{\text{out}}

  • Reason:
    This law is based on the conservation of electric charge — charge cannot accumulate at a junction, so whatever current flows in must flow out.

Example:

If 3 amps of current flows into a junction from one branch, and 2 amps flow in from another, then the total current flowing out must be 5 amps.

39. An electric current always produces a/an________field. [S.S.C. JE Electrical Exam 10.12.2020 (Shift-II)]

Correct Answer: (d) Magnetic
Solution:An electric current always produces a magnetic field.
  • The reason for creating a magnetic field is the movement of charges in an electric conductor.
  • The magnitude of the magnetic field produced around the conductor depends on the magnitude of the current flowing in the wire.
  • When the value of the electric current increases or decreases, the magnitude of the Magnetic field also increases or decreases.

40. Which one among the following is not an electromagnetic wave? [S.S.C. Online Graduation Level (T-I) 7.09.2016 (Shift-II)]

Correct Answer: (c) Cathode Ray
Solution:Those waves which do not require any medium for propagation and which can be transmitted even in a vacuum are called electromagnetic waves. So

me of the major electrical waves are

  • Gamma rays,
  • X-rays,
  • Ultraviolet waves,
  • Visible radiation,
  • Infrared rays, etc.

The cathode ray is not an electromagnetic ray.