Advertisements
Advertisements
प्रश्न
An electric kettle of 2 kW is used for 2h. Calculate the energy consumed in
- kilowatt hour and
- joules.
Advertisements
उत्तर
(i) Power, P = `"E"/"t"`
So, energy consumed, E = P × t = 2 × 2 = 4 kWh
(ii) Energy consumed, E = 4 kWh
= 4 × 1000 × 3600 J
= 1.44 × 107 J
APPEARS IN
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?
If the current flowing through a fixed resistor is halved, the heat produced in it will become:
Answer the following question:
what is the heating effect of the electric current? state any four applications of it?
What does overloading cause?
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.
- What is overloading?
- Is overloading and short the same? When does short-circuiting take place?
- How can the effects of overloading be avoided?
Find the odd one out.
In a set up the students coated iron nails with zinc metal and noted that, iron nails coated with zinc prevents rusting. They also observed that zinc initially acts as a physical barrier, but an extra advantage of using zinc is that it continues to prevent rusting even if the layer of zinc is damaged. Name this process of rust prevention and give any two other methods to prevent rusting.
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 ______.
