1000 identical drops of mercury are charged to a potential of 1 V each

1.	1000 identical drops of mercury are charged to a potential of 1 V each. They join to form a single drop. The potential of this drop will be (a) 0.01 V (b) 0.1 V (c) 10 V (d) 100 V
Answer» Correct Answer is: (d) 100 V Volume = 4/3 πR³ = 1000 x 4/3 πr³ or r = R/10 Q = CV = (4πε₀R) x V = 1000(4πε₀r) 1 or V = 10³ τ/R = 10³/10 = 100 V

1000 identical drops of mercury are charged to a potential of 1 V each. They join to form a single drop. The potential of this drop will be (a) 0.01 V (b) 0.1 V (c) 10 V (d) 100 V

Answer»

Correct Answer is: (d) 100 V

Volume = 4/3 πR³ = 1000 x 4/3 πr³ or r = R/10

Q = CV = (4πε₀R) x V = 1000(4πε₀r) 1

or V = 10³ τ/R = 10³/10 = 100 V

Discussion

No Comment Found

Related InterviewSolutions

Name a substance whose resistance almost remains unchanged by increase of temperature.
Two resistors with resistances `10 Omega and 15 Omega` are to be connected to a battery of `emf 12 V` so as to obtain : (i) minimum current (ii) maximum current. How will you connect the resistances in each case ? Calculate the strength of the total current in the circuit in the two cases.
An electric geyser has the rating `2000 W-220 V` marked on it. What should be the minimum current rating (in whole number) of the fuse-wire to be used ?
Assertion and Reason type questionAssertion: One kilowatt hour is known as one unit of electrical energy. Reason: 1 kWh = 3.6 × 106 J (a) If both the assertion and the reason are true and the reason is the correct explanation of the assertion. (b) If both the assertion and the reason are true, but the reason is not the correct explanation of the assertion. (c) If the assertion is true, but the reason is false. (d) If the assertion is false, but the reason is true.
Choose the correct statement: When the same current(i) flows through tow circuits as shown in the figures, then (assume that all bulbs are identical) (A) bulbs in first combination glow with more brightness. (B) bulbs in second combination glow with more brightness. (C) bulbs in both the combination glow with equal brightness. A. Only (A) is trueB. Only (B) is trueC. Only (C) is trueD. Cannot be determined.
400 J of heat is produced in 4 s in a 4 Ω resistor. Find potential difference across the resistor.
`100 J` of heat are produced each second in a `4 Omega` resistance. Find the potential difference across the resistor.
When a current of 4.0 A passes through a certain resistor for 10 minutes, 2.88 x 104 J of heat are produced. Calculate :(a) the power of the resistor.(b) the voltage across the resistor
Explain applications of heating effect.
Write Joule’s Law of Heating.

1000 identical drops of mercury are charged to a potential of 1 V each. They join to form a single drop. The potential of this drop will be (a) 0.01 V (b) 0.1 V (c) 10 V (d) 100 V

Discussion

No Comment Found

Related InterviewSolutions

Reply to Comment