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प्रश्न
Tara, after completing her exams, went to her grandmother's house along with her younger brother Rahul. One day, Rahul came home after playing and switched on the fan and air conditioner. At the same time, his grandmother was preparing a milkshake for him using a mixer. Suddenly, they heard a big sound and the electricity of the house got shut down. Tara is called an electrician. He said the main reason for supply to shut down was overloading.
- What is overloading?
- Is overloading and short the same? When does short-circuiting take place?
- How can the effects of overloading be avoided?
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उत्तर
- Overloading is the term used to describe the circuit's current flow when it exceeds the allowed value.
- Short-circuiting and overloading are not the same. When a live wire and a neutral wire are in direct contact with one another, a short circuit occurs.
- Overloading can be avoided by not connecting too many appliances to the same circuit at the same time.
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संबंधित प्रश्न
Why does the cord of an electric heater not glow while the heating element does?
An electric iron of resistance 20 Ω takes a current of 5 A. Calculate the heat developed in 30 s.
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Explain why, tungsten is used for making the filaments of electric bulbs.
Explain why, the current that makes the heater element very hot, only slightly warms the connecting wires leading to the heater.
The heat produced by passing an electric current through a fixed resistor is proportional to the square of:
(a) magnitude of resistance of the resistor
(b) temperature of the resistor
(c) magnitude of current
(d) time for which current is passed
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Give Scientific reason.
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Identify the figure and give its use.
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Statement 2 : Heat in the resistor is created according to the rule of energy conservation.
Explain Statement 1 with the help of Statement 2.
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A coil of an alloy _______ is used in electric heater cooker as a resistor.
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Mark the correct choice
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Name the effect of the current responsible for the glow of the bulb in an electrical circuit.
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A fuse is used in an electric circuit to stop high currents flowing through the circuit.
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What is the heating effect of electric current?
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