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Electricity

What is the commercial unit of electrical energy? Represent it in terms of joules.

07/11/2024

Science

10th

Electricity

What is electrical resistivity? In a series electrical circuit comprising a resistor made up of a metallic wire, the ammeter reads 5 A. The reading of the ammeter decreases to half when the length of the wire is doubled. Why?

07/11/2024

Science

10th

Electricity

How does use of a fuse wire protect electrical appliances?

07/11/2024

Science

10th

Electricity

Draw a circuit diagram of an electric circuit containing a cell, a
key, an ammeter, a resistor of 2 Ω in series with a combination
of two resistors (4 Ω each) in parallel and a voltmeter across the
parallel combination. Will the potential difference across the 2 Ω
resistor be the same as that across the parallel combination of
4Ω resistors? Give reason.

07/11/2024

Science

10th

Electricity

Three 2 Ω resistors, A, B and C, are connected as shown in Figure. Each of them dissipates energy and can withstand a maximum power of 18W without melting. Find the maximum current that can flow through the three resistors?

07/11/2024

Science

10th

Electricity

A child has drawn the electric circuit to study Ohm’s law as shown in Figure. His teacher told that the circuit diagram needs correction. Study the circuit diagram and redraw it after making all corrections.

07/11/2024

Science

10th

Electricity

Unit of electric power may also be expressed as
(a) volt ampere
(b) kilowatt hour
(c) watt second
(d) joule second

07/11/2024

Science

10th

Electricity

Two resistors of resistance 2 Ω and 4 Ω when connected to a battery will have
(a) same current flowing through them when connected in parallel
(b) same current flowing through them when connected in series
(c) same potential difference across them when connected in series
(d) different potential difference across them when connected in parallel

07/11/2024

Science

10th

Electricity

An electric kettle consumes 1 kW of electric power when operated at 220 V. A fuse wire of what rating must be used for it?
(a) 1 A
(b) 2 A
(c) 4 A
(d) 5 A

07/11/2024

Science

10th

Electricity

In an electrical circuit two resistors of 2 Ω and 4 Ω respectively are connected in series to a 6 V battery. The heat dissipated by
the 4 Ω resistor in 5 s will be
(a) 5 J
(b) 10 J
(c) 20 J
(d) 30 J

07/11/2024

Science

10th