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महाराष्ट्र राज्य शिक्षण मंडळएस.एस.सी (इंग्रजी माध्यम) इयत्ता १० वी

Write scientific reason. A coil made up of alloy Nichrome is used in the electric heater cooker as a resistor. - Science and Technology 1

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प्रश्न

Write scientific reason.

A coil made up of alloy Nichrome is used in the electric heater cooker as a resistor.

स्पष्ट करा
टीपा लिहा
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उत्तर

  1. The electric heater-cooker works on the principle of heating effect of electric current.
  2. Alloys (such as nichrome) as compared to metals have higher resistivity.
  3. Unlike metals they can be heated to higher temperature.
    Hence, a coil made up of alloy nichrome is used in the electric heater-cooker as a resistor.
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  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 4: Effects of electric current - Write scientific reasons

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संबंधित प्रश्‍न

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(b) How much energy is transferred to the heater each second?


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The current passing through a room heater has been halved. What will happen to the heat produced by it?


Name the material which is used for making the filaments of an electric bulb.


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(a) half
(b) double
(c) four time
(d) one-fourth 


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(a) chemical effect of current
(b) magnetic effect of current
(c) lighting effect of current
(d) heating effect of current


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(a) thin and short
(b) thick and short
(c) low melting point
(d) higher resistance than rest of wiring


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P `6.84xx10^8`Ωm
Q `1.70xx10^8`Ωm  
R ` 1.0xx10^15`Ωm
s  `11.0xx10^-7`Ωm  

Which material will you use for making: (a) heating element of electric iron (b) connecting wires of electric iron (c) covering of connecting wires? Give reason for your choice in each case.

 


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A Nail 3.0 3.15
B Thin plate 6.0 6.33

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Anannya responded to the question: Why do electrical appliances with metallic bodies are connected to the mains through a three-pin plug, whereas an electric bulb can be connected with a two-pin plug?

She wrote: Three-pin connections reduce heating of connecting wires.

  1. Is her answer correct or incorrect? Justify.
  2. What is the function of a fuse in a domestic circuit?

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