The frequency of alternating current (AC) supply in India is ……………..
A) 0Hz
B) 50 Hz
C) 60 Hz
D) 100 Hz
1 Answers
A train, standing at the outer signal of a railway station blows a whistle of frequency 400 Hz in still air. (i) What is the frequency of the whistle
Given: vs = 10 m/s, v = 340 m/s, n0 = 400 Hz Apparent frequency (n), velocity of sound (vs) in each case Formulae: i. n = n0 \((\frac{v}{v-v_s})\) ii. n = n0 \(\frac{v}{v+v_s}\) Calculation: a. As the train approaches the...
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A stationary source produces a note of frequency 350 Hz. An observer in a car moving towards the source measures the frequency
Given: n0 = 350 Hz, v = 340 m/s, nA = 370 Hz To find: Speed (vL), Frequency (nA) Formulae: i. When the car moves towards the stationary source then, nA = n0 \((\frac{v+v_s}{v})\) ii. When the car moves away from...
2 Answers 1 views
Alternating of crops preserve the A) Soil fertility
A) Soil fertility
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The frequency of direct current is …………………
Correct option is A) 0 Hz
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A metal wire of radius 0.4 mm carries a current of 2 A. Find the magnitude of current density if the current is assumed to be uniformly distributed
Given: r = 0.4 mm = 0.4 × 10-3 m, I = 2 A To find: Current density (J) Formula: J = \(\frac{I}{A}\) Calculation: From formula, J = \(\frac{2}{3.142\times(0.4)^2\times10^{-6}}\) = 3.978 × 106 A/m2
2 Answers 134 views
Calculate the current flowing through a heater rated at 2 kW when connected to a 300 V d. c. supply.
Given: P = 2 kW = 2000 W, V = 300 V To find: Current (I) Formula: P = IV Calculation: From formula, I = \(\frac{P}{V}=\frac{2000}{300}\) = 6.67 A
2 Answers 1 views
An electric heater takes 6 A current from a 230 V supply line, calculate the power of the heater and electric energy consumed by it in 5 hours.
Given: I = 6 A, V = 230 V, t = 5 hours To find: Power (P), Energy consumed Formulae: i. P = IV ii. Energy consumed = power × time Calculation: From formula...
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The process of superimposing a low frequency signal on a high frequency wave is ……………
Correct option is: (C) modulation
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The method in which crops are planted in alternating strips across a slope or across the path of the prevailing wind is……
B) Contour strips
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A bus is moving towards a huge wall with a velocity of `5m//s^(-1)`. The driver sounds a horn of frequency `200 Hz`. The frequency of the beats heard
Correct Answer - 6 Hz
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