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Question

Difficulty: HardIce and Snow Conditions

Activating cruise control when driving on roads affected by ice and snow helps maintain vehicle control by preventing erratic throttle inputs and stabilizing wheel rotation.

Answer: Answer

Answer

False (Cruise control should never be used in icy or snowy conditions because it can maintain power delivery during traction loss and cause a severe skid).
The correct answer is False. On roads affected by ice and snow, tyre grip is minimal and unpredictable. Cruise control systems continuously regulate engine power to maintain a preset speed. If the drive wheels encounter ice and break traction, cruise control can continue applying power or accelerate to sustain the set speed, resulting in violent wheel spin and a severe loss of directional control. Additionally, using cruise control prevents the driver from instantly exploiting natural engine braking by lifting off the accelerator pedal.

Step-by-Step Solution

1
Examine how vehicle cruise control operates in standard driving conditions.
Cruise control continuously regulates the throttle to maintain a set speed without requiring manual accelerator pedal input.
Understanding the automated mechanism of the system is essential to evaluate its interaction with slippery surfaces.
2
Analyze tyre grip dynamics and surface friction variations on ice- and snow-covered roads.
Traction on snow and ice is drastically reduced and can change instantaneously between patchy grip and zero friction.
Sudden loss of surface friction directly affects how driven wheels respond to engine torque.
3
Evaluate vehicle handling and stability risks when cruise control remains active across low-grip surfaces.
If the driven wheels slip on ice, the system detects a loss of speed and can apply additional power, spinning the drive wheels and precipitating an immediate, uncontrolled skid while delaying driver intervention via engine braking.
Driver assistance systems designed for dry tarmac cannot anticipate loss of surface adhesion and can exacerbate vehicle instability.
4
Determine the validity of the statement based on UK vehicle handling principles.
The statement is determined to be false; drivers must retain full manual control of throttle and gears in winter conditions.
Manual control allows immediate reduction of torque and gentle application of engine braking at the first sign of traction loss.

Key Concept

Handling risks and the prohibition of cruise control systems on ice and snow
Estimated Time:1m 0s
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Topics

Ice and Snow Conditions

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