Assignment 4
1. Complete the table below. Assume that 1 unit of electricity costs 12p
| Device | Power (kW) | time (hours) | Units used (kWh) | Cost (p) |
| lamp | 0.1 | 10 | ||
| television | 0.4 | 8 | ||
| kettle | 3 | 2 | ||
| vacuum cleaner | 2 | 0.5 | ||
| computer | 0.3 | 5 | ||
| heater | 2.5 | 6 |
2. A farmer installs a wind turbine on his farm to generate electricity. Study the data given then answer the questions.
Average power output = 1.4 kW Hours per year of suitable wind = 2000
Cost of 1 unit of electricity = 12p Cost of turbine = £1,200
a) How many units of electricity should be generated in a year?
b) How much would the farmer normally pay for this much electricity?
c) How long should it take for the turbine to pay for itself?
d) What other factors should one consider before installing a wind turbine?