हिंदी

Find the odd one out and give its explanation. Potassium, Magnesium, Calcium, Beryllium - Science and Technology 1

Advertisements
Advertisements

प्रश्न

Find the odd one out and give its explanation.

विकल्प

  • Tungsten

  • Nichrome

  • Aluminium

  • Iron

MCQ
Advertisements

उत्तर

Nichrome

Explanation-

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

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 4: Effects of electric current - Find odd one out.

APPEARS IN

संबंधित प्रश्न

When current is switched ‘on’ in a room heater, it ______.


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

(a) How much charge flows around the circuit each second?


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

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


Why are the coils of electric irons and electric toasters made of an alloy rather than a pure metal?


Why is a series arrangement not used for connecting domestic electrical appliances in a circuit?


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


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


The heat produced in a wire of resistance 'x' when a current 'y' flows through it in time 'z' is given by:

(a) x2 × y × z
(bx × z × y2
(cy × z2 × x
(dy × z × 


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


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


Give Scientific reason.

In practice, the unit kWh is used for the measurement of electrical energy, rather than joule.


Identify the figure and give its use.


Heat energy is being produced in a resistance in a circuit at the rate of 100 W. The current of 3 A is flowing in the circuit. What must be the value of the resistance?


An electric iron of 1100 W is operated for 2 hrs daily. What will be the electrical consumption expenses for that in the month of April? (The electric company charges Rs 5 per unit of energy).


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.


Answer the following question:
what is the heating effect of the electric current? state any four applications of it?


Which of the following substance contracts on heating?


Live wire and neutral wires have a 220 V potential difference.


Write scientific reason.

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


Explain the importance/uses of fuse wire.


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


The heating element of an electric iron is made up of:


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


An electric kettle consumes 1 kW of electric power when operated at 220 V. A fuse wire of what rating must be used for it?


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


Paheli took a wire of length 10 cm. Boojho took a wire of 5 cm of the same material and thickness. Both of them connected the wires as shown in the circuit given in the following figure. The current flowing in both the circuits is the same.

  1. Will the heat produced in both cases be equal? Explain.
  2. Will the heat produced be the same if the wires taken by them are of equal lengths but of different thickness? Explain.


What is an electric fuse made up of?


What are the factors affecting heating effect of electric current?


Fuse is a strip of alloy wire which is made up of lead and tin with a very low ______.


Name a few appliances which work on the basis of the heating effect of current.


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.


When a current I flows through a wire of resistance R for time t then the electrical energy produced is given by ______.


An electric iron of resistance 20 Ω draws a current of 5 A. The heat developed in the iron in 30 seconds is ______.


An electric iron is rated 220 V, 2 kW. If the iron is used for 3h daily find the cost of running it for one week if it costs ₹ 4.25 per kWh.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×