Safe and Economical Driving
Which accessory increases air resistance and therefore fuel consumption at high speeds?
Reviewed on 29 Jul 2026
- ✓ A loaded roof rack
- B The rear head restraints
- C The interior rear-view mirror
- D The spare wheel in the boot
Why this is the correct answer
A roof rack increases aerodynamic resistance; it is better to carry luggage in the boot to reduce consumption.
More questions on Safe and Economical Driving
- Driving at speed on an interurban road with the windows down:
- Regarding tyres, what directly affects fuel consumption?
- Regular vehicle servicing (filters, spark plugs, tyre pressure):
- Why does a vehicle consume more fuel driving in the city than on the open road, despite going slower?
- Why is going downhill in neutral NOT a safe fuel-saving measure?
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