हिंदी
तमिलनाडु बोर्ड ऑफ सेकेंडरी एज्युकेशनएसएसएलसी (अंग्रेजी माध्यम) कक्षा १०

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?

Advertisements
Advertisements

प्रश्न

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?

योग
Advertisements

उत्तर

Case: 1
Power (P) = 420W
Applied Voltage (V) = 220V
Current \(\mathrm{I}=\frac{\mathrm{P}}{\mathrm{V}}=\frac{420}{220}=1.9 \mathrm{A}\)

Case: 2
Power (P) = 180 W
Applied Voltage (V) = 2.20 V
Current \(\mathrm{I}=\frac{\mathrm{P}}{\mathrm{V}}=\frac{180}{220}=0.8 \mathrm{A}\)

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 4: Electricity - Evaluation [पृष्ठ ५७]

APPEARS IN

सामाचीर कलवी Science [English] Class 10 SSLC TN Board
अध्याय 4 Electricity
Evaluation | Q IX. 1. | पृष्ठ ५७

संबंधित प्रश्न

Why are the conductors of electric heating devices, such as bread-toasters and electric irons, made of an alloy rather than a pure metal?


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?


Give a scientific reason:

For electric power transmission, copper or aluminium wire is used.


An electric iron draws a current of 4 A when connected to 220 V mains. Its resistance must be:


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


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.

Copper wire offers very little ______ and does not get heated up quickly.


If 220 V potential difference is applied across an electric bulb, a current of 0.45 A flows in the bulb. What must be the power of the bulb?


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?

Two students decided to investigate the effect of water and air on iron object under identical experimental conditions. They measured the mass of each object before placing it partially immersed in 10 ml of water. After a few days, the object were removed, dried and their masses were measured. The table shows their results.

Student Object Mass of Object
before Rusting in g
Mass of the coated
object in g
A Nail 3.0 3.15
B Thin plate 6.0 6.33

What might be the reason for the varied observations of the two students?


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×