Advertisements
Advertisements
Questions
How many milliamperes as there in 1 ampere?
1 ampere = 1000 milliamperes =`10^3` milliamperes
Advertisements
Solution
1 ampere = 1000 milliamperes =`10^3` milliamperes
APPEARS IN
RELATED QUESTIONS
Why should the resistance of:
a voltmeter be very large?
In 10 s, charge of 25 C leaves a battery, and 200 J of energy are delivered to an outside circuit a result.
What is the p.d. across the battery?
One coulomb of charge flows through any cross-section of a conductor in 1 second. What is the current flowing through the conductor?
(a) With the help of a circuit diagram, obtain the relation for the equivalent resistance of two resistances connected in parallel.
(b) In the circuit diagram shown below, find:
(i) Total resistance.
(ii) Current shown by the ammeter A
What happens to the other bulbs in a parallel circuit if one bulb blows off?
Distinguish between an open and a closed circuit.
The following table shows the current in Amperes and potential differences in Volts.
- Find the average resistance.
- What will be the nature of the graph between the current and potential difference? (Do not draw a graph.)
- Which law will the graph prove? Explain the law.
| V (volts) | I (amp) |
| 4 | 9 |
| 5 | 11.25 |
| 6 | 13.5 |
Complete the following sentence:
A fuse is connected in ........... with the ......... wire.
Fig. shows a 3 pin plug with the cover removed. The electric cable
connected to the plug contains 3 wires with colour coded insulation namely brown, blue and green.
- Identify each of the colour coded wires by stating to which of the
terminals A, B or C in the diagram they should be connected. - Identify the terminal through which no current passes in normal
circumstances. - What is the purpose of the earthed wire connected to an electric
appliance like an electric heater? Describe how it works.
Electrical appliances have voltage and power ratings as listed below. Which
has the larger working resistance?
| Appliances | Voltage (V) | Power (W) |
| (a) Washing machine | 250 | 3000 |
| ( b) Television | 240 | 160 |
| (c)240 | 240 | 1500 |
| ( d) Hair curler | 250 | 20 |
| ( e) Car head lamp | 12 | 36 |
What is the function of a step-up transformer?
Define the term kilowatt - hour and state its value in S.I. unit.
An electric bulb is rated at 220 V, 100 W.
- What is its resistance?
- What safe current can be passed through it?
An electric kettle is rated 2.5 kW, 250 V. Find the cost of running the kettle for two hours at Rs. 5.40 per unit.
Explain, why the potential difference across the terminals of a cell is more when the cell is not in use than it is when the cell is being used.
Electric current passes through a metallic conductor due to the movement of ______.
