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प्रश्न
What does overloading cause?
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उत्तर
Due to overloading, fuse wire melts and the supply gets shut down.
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संबंधित प्रश्न
How does the resistance of a wire vary with its area of cross-section?
Write Joule's law of heating.
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- How much energy is transferred to the heater each second?
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diameter?
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Explain why, the current that makes the heater element very hot, only slightly warms the connecting wires leading to the heater.
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Derive the expression for the heat produced due to a current 'I' flowing for a time interval 't' through a resistor 'R' having a potential difference 'V' across its ends. With which name is this relation known?
How much heat will an instrument of 12 W produce in one minute if it is connected to the heat produced by it?
The current passing through a room heater has been halved. What will happen to the heat produced by it?
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(a) x2 × y × z
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(c) y × z2 × x
(d) y × z × x
The electrical resistivities of four materials P, Q, R and S are given below:
| P | `6.84xx10^8`Ωm |
| Q | `1.70xx10^8`Ωm |
| R | ` 1.0xx10^15`Ωm |
| s | `11.0xx10^-7`Ωm |
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Statement 2 : Heat in the resistor is created according to the rule of energy conservation.
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what is the heating effect of the electric current? state any four applications of it?
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Right or wrong sentence.
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Which of the following is correct?
Mark the correct choice
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SFEU
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- Will the heat produced be the same if the wires taken by them are of equal lengths but of different thickness? Explain.
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Find the odd one out.
Two students decided to investigate the effect of water and air on iron object under identical experimental conditions. They measured the mass of each object before placing it partially immersed in 10 ml of water. After a few days, the object were removed, dried and their masses were measured. The table shows their results.
| Student | Object | Mass of Object before Rusting in g |
Mass of the coated object in g |
| A | Nail | 3.0 | 3.15 |
| B | Thin plate | 6.0 | 6.33 |
What might be the reason for the varied observations of the two students?
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- kilowatt hour and
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State the law that explains the heating effect of current with respect to the measurable properties in an electrical circuit.
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