Advertisements
Advertisements
प्रश्न
उत्तर
Given, P = 100 W, p.d. = 220 V
We know that,
P = `"V"^2/"R"`
P = `"V"^2/"R" = *(220)^2/100 = 484 Omega`
Also, we know that,
P=VI
I = `"P"/"V" = 100/220 = 0.45`A
Thus a fuse of rating 7A may be used with the appliance and it should be connected in the live wire before connectimg it to the appliance
APPEARS IN
संबंधित प्रश्न
Three 2 V cells are connected in series and used as a battery in a circuit.
What is the p.d. at the terminals of the battery?
What is an Ammeter? How is It Connected in a Circuit? Draw a Diagram to Illustrate Your Answer.
For a heater rated at 4 kW and 220 V, calculate:
(a) the current,
(b) the resistance of the heater,
(c) the energy consumed in 2 hours, and
(d) the cost if 1 kWh is priced at Rs 4.60.
Three resistors of 6.0 𝛀, 2.0𝛀 and 4.0𝛀 are joined to an ammeter A and a cell of e.m.f. 6.0 V as
shown in fig 8.52 Calculate:
(a) the effective resistance of the circuit and
(b) the reading of ammeter.
A bulb marked 12 V, 24 W operates on a 12 V battery for 20 minutes. Calculate:
- The current flowing through it, and
- The energy consumed.
A battery of e.m.f. 15 V and internal resistance 2 Ω is connected to two resistors of resistances 4 ohm and 6 ohm joined (a) in series. Find in each case the electrical energy spent per minute in 6 Ω resistor.
Kilowatt hour is the unit of
The power of an electric device is a product of ______ and ______.
The SI unit for electric current is the coulomb.
