A variable is a quantity that can take on a range of values.

A formula is a rule linking sets of physical variables in context.

An average is a single number expressing the central or typical value in a set of data: the mode; the median; and the mean.

Solar power

Maths

Maths and the environment

A house has a set of 5 solar panels. Each panel produces 1.08 kWh of electricity per day. In total, the set of 5 panels produce {{}} kWh of electricity per day.

A home owner spends £10 200 on solar panels. The panels save £1275 per year on electricity bills. How many years will it take for the annual savings to cover the cost of the solar panels?

In ideal conditions, a solar panel would generate 1.4 kWh of electricity per day. However, its performance is reduced so that it produces 30% less electricity. Therefore, it produces {{}} kWh per day.

The average cost of electricity could be calculated as: 24.5 p per kWh consumed + 60 p daily standing charge. For a house that uses 8 kWh of electricity per day, the cost would be £{{}} per day.

The formula calculates the amount of electricity produced by a solar panel.
A solar panel has a power rating of 450 watts.
With 5 hours of peak sunlight, the panel produces {{}} kWh of electricity.

A __________ is a rule linking sets of physical variables in context.

Which calculations would decrease 540 by 20%?

Substitute $$x=4.9$$ into the expression $$24.5x + 60$$.

$$E = PH$$. Calculate the value of $$E$$ when $$P = 0.35$$ and $$H = 3$$. Give the exact value, without rounding.

Starter Quiz