मराठी

Paheli took a wire of length of 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 Figure 14.4. - Science

Advertisements
Advertisements

प्रश्न

Paheli took a wire of length of 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 Figure 14.4. The current flowing in both circuits is the same.

(i) Will the heat produced in both cases be equal? Explain

(ii) Will the heat produced be the same if the wires taken by them are of equal lengths but of different thicknesses? Explain.

थोडक्यात उत्तर

उत्तर

(i) No, the amount of heat produced in both cases will not be equal. The amount of heat produced in a wire depends upon the length of the wire.

(ii) No, the amount of heat produced in the wire depends upon the thickness of the wire.

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 14: Electric Current and Its Effects - LONG ANSWER QUESTIONS [पृष्ठ ७८]

APPEARS IN

एनसीईआरटी एक्झांप्लर Science [English] Class 7
पाठ 14 Electric Current and Its Effects
LONG ANSWER QUESTIONS | Q 18. | पृष्ठ ७८

संबंधित प्रश्‍न

How does the resistance of a wire vary with its: 

 diameter? 

 


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


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. 


Solve the following example.

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?


Solve the following example.

Two tungsten bulbs of wattage 100 W and 60 W power work on 220 V potential difference. If they are connected in parallel, how much current will flow in the main conductor? 


Three incandescent bulbs of 100 W each are connected in series in an electric circuit. In another circuit another set of three bulbs of the same wattage are connected in parallel to the same source.

  1. Will the bulb in the two circuits glow with the same brightness? Justify your answer.
  2. Now let one bulb in both the circuits get fused. Will the rest of the bulbs continue to glow in each circuit? Give reason.

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.


Name the effect of the current responsible for the glow of the bulb in an electrical circuit.


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 ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×