Eco-Driving & Fuel Efficiency Flashcards
6 cards from real CPC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Eco-Driving & Fuel Efficiency flashcards as text
Which driving technique most significantly reduces fuel consumption on a long motorway journey?
Answer: Using cruise control to maintain a steady speed and anticipating traffic flow to avoid unnecessary braking
Smooth, consistent speed — maintained using cruise control and anticipation to avoid harsh braking and acceleration — is the single biggest factor in reducing fuel consumption on motorways.
How does tyre pressure affect fuel economy?
Answer: Under-inflated tyres increase rolling resistance, increasing fuel consumption by up to 3% per 10% under-inflation
Under-inflation increases rolling resistance as more tyre sidewall is in contact with the road; this directly increases the energy (fuel) required to maintain speed.
What does 'anticipatory driving' mean in an eco-driving context?
Answer: Reading traffic situations well ahead and adjusting speed smoothly to avoid unnecessary stop-start driving
Anticipatory driving uses early perception of traffic conditions to decelerate gently and avoid braking fully, allowing momentum to be used efficiently and reducing fuel waste.
Idling the engine of an HGV for extended periods is discouraged because:
Answer: It wastes significant fuel (approximately 2 litres/hour), increases emissions and can cause engine carbon build-up
An idling HGV engine typically consumes 2–3 litres of fuel per hour, producing unnecessary CO₂ and NOx emissions; switching off when stationary for more than 2 minutes is best practice.
What is the effect on fuel consumption of increasing motorway speed from 56 mph to 60 mph?
Answer: A significant increase of approximately 10-15% due to the cubic relationship between air resistance and speed
Aerodynamic drag increases with the cube of speed; a relatively small speed increase above 56 mph causes a disproportionately large increase in fuel consumption.
How does carrying excess payload weight above the planned load affect fuel consumption?
Answer: Every extra tonne increases fuel consumption by approximately 1-2%, increasing running costs and emissions
Extra weight directly increases the engine's workload on hills and in acceleration, increasing fuel consumption; careful load planning to avoid deadweight reduces operating costs.