हिंदी

Find the odd one out and give its explanation. Potassium, Magnesium, Calcium, Beryllium

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प्रश्न

Find the odd one out and give its explanation.

विकल्प

  • Tungsten

  • Nichrome

  • Aluminium

  • Iron

MCQ
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उत्तर

Nichrome

Explanation-

Nichrome is an alloy used for making wires, while others are soft metals.

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  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 4: Effects of electric current - Find odd one out. [पृष्ठ १२]

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एससीईआरटी महाराष्ट्र Science and Technology Part 1 [English] Standard 10 Maharashtra State Board
अध्याय 4 Effects of electric current
Find odd one out. | Q 3. | पृष्ठ १२

संबंधित प्रश्न

An electric iron of resistance 20 Ω takes a current of 5 A. Calculate the heat developed in 30 s.


How does the resistance of a wire vary with its area of cross-section?


An electric heater is connected to the 230 V mains supply. A current of 8 A flows through the heater.

  1. How much charge flows around the circuit each second?
  2. How much energy is transferred to the heater each second?

Explain why, the current that makes the heater element very hot, only slightly warms the connecting wires leading to the heater.


 How much heat will an instrument of 12 W produce in one minute if it is connected to the heat produced by it?  


What is meant by the heating effect of current?


The elements of electrical heating devices are usually made of:

(a) tungsten
(b) bronze
(c) nichrome
(d) argon


If the current flowing through a fixed resistor is halved, the heat produced in it will become:


An electric iron is connected to the mains power supply of 220 V. When the electric iron is adjusted at ‘minimum heating' it consumes a power of 360 W but at 'maximum heating’ it takes a power of 840 W. Calculate the current and resistance in each case.


Which electric heating device in your home do you think have resistors which control the flow of electricity?


Identify the figure and give its use.


Statement 1 : Electric current ( flow of electrons ) creates heat in the resistor.
Statement 2 : Heat in the resistor is created according to the rule of energy conservation.
Explain Statement 1 with the help of Statement 2.


Give scientific reason :
In the electric equipment producing heat e.g. iron, electric heater, boiler, toaster, etc., an alloy such as Nichrome is used, not pure metals.


A coil of an alloy _______ is used in electric heater cooker as a resistor.


Which metal is used to make the filament of an electric bulb?


What is a short circuit?


Explain the application of heating effect of electric current in an electric bulb with a diagram.


Heating effect of current is called ______


Which of the following is correct?


An electric iron consumes energy at the rate of 420 W when heating is at the maximum rate and 180 W when heating is at the minimum rate. The applied voltage is 220 V. What is the current in each case?


A current of 1 A is drawn by a filament of an electric bulb. Number of electrons passing through a cross-section of the filament in 16 seconds would be roughly:


An electric bulb is connected to a 220 V generator. The current is 0.50 A. What is the power of the bulb?


How does use of a fuse wire protect electrical appliances?


Why is parallel arrangement used in domestic wiring?


(a) Observe the diagram given below and state whether the bulb will glow or not when we switch on K.

(b) Is it safe to handle the bulb when the switch is OFF?

(c) Give a reason for your answer in (b).


An electric component used as a safety device is electric circuit is ______.


Unscramble the following words:

SFEU


An electric fuse has a body made of ceramic and two points for connecting the fuse wire.


Explain the working of an electric fuse.


It would cost a man Rs. 3.50 to buy 1.0 kW h of electrical energy from the Main Electricity Board. His generator has a maximum power of 2.0 kW. The generator produces energy at this maximum power for 3 hours. Calculate how much it would cost to buy the same amount of energy from the Main Electricity Board.


Assertion: A current-carrying wire should be charged.
Reason: The current in a wire is due to the flow of free electrons in a definite direction.


A student boils water in an electric kettle for 20 minutes. Using the same mains supply he wants to reduce the boiling time of water. To do so should he increase or decrease the length of the heating element? Justify your answer.


An electrochemical cell converts ______ energy into ______ energy.


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.

  1. What is overloading?
  2. Is overloading and short the same? When does short-circuiting take place?
  3. How can the effects of overloading be avoided?

1 kWh is equal to ______.


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