Question map
Not attempted Correct Incorrect ★ Bookmarked
Loading…
Q94 (CDS-II/2011) Science & Technology › Basic Science (Physics, Chemistry, Biology) › Electricity and magnetism Answer Verified

When you pull out the plug connected to an electrical appliance, you often observe a spark. To which property of the appliance is this related ?

Result
Your answer: —  Â·  Correct: B
Explanation

The spark observed when pulling out a plug is primarily due to the property of inductance. According to Faraday's Law of Induction, when the circuit is suddenly broken, the current drops rapidly to zero, causing a collapsing magnetic field [t1][t7]. This rapid change in magnetic flux induces a high 'back EMF' or 'inductive kickback' [t1][t3]. This induced voltage is often high enough to ionize the air between the plug and the socket, resulting in a visible spark or arc [t2][t4]. While resistance and wattage relate to the heating and power consumption of the appliance [c1][c3], they do not cause this specific electromagnetic discharge. Inductance is inherent in any appliance with coils or motors, such as fans or refrigerators, which store energy in their magnetic fields [t6][t7].

Sources

  1. [1] Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 4: Electricity: Magnetic and Heating Effects > A step further > p. 54
  2. [2] Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 4: Electricity: Magnetic and Heating Effects > Think like a scientist > p. 53
How others answered
Each bar shows the % of students who chose that option. Green bar = correct answer, blue outline = your choice.
Community Performance
Out of everyone who attempted this question.
25%
got it right
✓ Thank you! We'll review this.

SIMILAR QUESTIONS

NDA-II · 2016 · Q80 Relevance score: -4.74

The property of electric current which is applicable in the fuse wire is

NDA-II · 2018 · Q42 Relevance score: -6.47

The connecting cable of electrical appliances like electric iron, water heater or contains three insulated copper wires of three different colours- red, green and black. Which one of the following is the correct colour code?

NDA-II · 2016 · Q63 Relevance score: -7.22

When three resistors, each having resistance ry are connected in parallel, their resultant resistance is .x. If these three resistances are connected in series, the total resistance will be

IAS · 1998 · Q108 Relevance score: -7.32

A fuse is used in main electric supply as a safety device. Which one of the following statements about the fuse is correct?

NDA-I · 2016 · Q42 Relevance score: -7.44

A simple circuit contains a 12 V battery and a bulb having 24 ohm resistance. When you turn on the switch, the ammeter connected in the circuit would read