A car is travelling at 20\text{ mph} along an ungritted side street covered with packed ic… — UK Driving Theory Test

A car is travelling at $20\text{ mph}$ along an ungritted side street covered with packed ice and snow. In normal dry conditions, the average total stopping distance at $20\text{ mph}$ is $12\text{ metres}$ . According to The Highway Code, stopping distances on icy surfaces can increase by up to ten times ( $10\times$ ). By how many metres does the total stopping distance increase when stopping on ice compared to normal dry conditions at this speed?

Answer: 108 metres

Answer

The total stopping distance increases by

108\text{ metres}

According to The Highway Code, stopping distances in icy conditions can be up to ten times longer than on dry roads. At

20\text{ mph}

, the standard dry stopping distance is

12\text{ metres}

, meaning the stopping distance on ice can reach

12\text{ m} \times 10 = 120\text{ metres}

. The increase over dry tarmac is therefore

120\text{ m} - 12\text{ m} = 108\text{ metres}

(or

12\text{ m} \times 9 = 108\text{ m}

Step-by-Step Solution

Calculate the total stopping distance on ice

12\text{ m} \times 10 = 120\text{ m}

The Highway Code states that overall stopping distances can increase by up to ten times on ice and snow.

Subtract the dry stopping distance from the icy stopping distance to find the increase

120\text{ m} - 12\text{ m} = 108\text{ m}

The question asks for the additional distance (the increase) rather than the total stopping distance on ice.

Key Concept

Highway Code stopping distance multipliers for ice and snow

Estimated Time:1m 0s

Question

Answer

Step-by-Step Solution

Key Concept

Common Mistakes

Topics

More questions from this topic