Advertisements
Advertisements
प्रश्न
An electrical appliance is rated 1500 W, 250 V. This appliance is connected to 250 V mains. Calculate:
(i) the current drawn,
(ii) the electrical energy consumed in 60 hours,
(iii) the cost of electrical energy consumed at Rs. 2.50 per kWh.
Advertisements
उत्तर
(i) Since, W = V × i, But given that W = 1500, V = 250
Current, i = `"W"/"n"`
`= 1500/250 = 6` amperes
(ii) Energy consumed in 60 hours
`= ("Watts" xx "hours")/1000` kWh
`= (1500 xx 60)/1000 = 90` kWh
(iii) Cost of 90 kWh at Rs. 2.50/kWh = Rs. 90 × 2.50 = Rs. 225.00.
संबंधित प्रश्न
1 kWh = ________ J
When an electric lamp is connected to 12 V battery, it draws a current of 0.5 A. The power of the lamp is:
(a) 0.5 W
(b) 6 W
(c) 12 W
(d) 24 W
1kWh = …….. J
Two bulbs are rated 60 W, 220 V and 60 W, 110 V respectively. Calculate the ratio of their
resistances
Water in an electric kettle connected to a 220 V supply took 5 minutes to reach its boiling point. How long would it have taken if the supply voltage had fallen to 200 V?
What is wrong with the circuit diagram (Fig. 34)? Carefully check the symbols and assign proper positive and negative signs to them.
The diagram shows a coil connected to a center zero galvanometerG . The galvanometer shows a deflect ion to the right when the north pole N of a powerful magnet is moved to the right as shown .
(i) Explain, why the defelct ion occurs in the galvanometer.
(ii ) State whether th e current in the coil is cl ockwise or anticl ockwise
when viewed from the end P.
(iii ) State th e observation in G when the coil is moved away from north
pole N of the magnet keeping the magnet stationary.
(iv)State the observation in G when both the coil and the magnet are
moved to right at th e same speed .
State three factors on which the heat produced in a metallic wire due to passage of current in it depends.
Why is heating element wound on a long porcelain rod in a room heater.
