Verification of truth — everyday physics (inertia & braking): “A boy riding a bicycle applies the brakes suddenly; he bends forward.” Choose the most accurate frequency statement.

Difficulty: Easy

Correct Answer: Generally

Explanation:


Introduction / Context:
This item checks basic Newtonian intuition. When a cyclist brakes hard, the bicycle experiences a rapid deceleration. Due to inertia, the rider’s upper body tends to continue moving forward, producing a forward bend or pitch.



Given Data / Assumptions:

  • “Sudden braking” implies high negative acceleration.
  • Normal upright bicycle posture, no unusual restraints (e.g., harness).
  • Usual road conditions; front brake engagement can cause pitch-forward torque.


Concept / Approach:
Newton’s first law (inertia) states a body continues its state of motion unless acted upon by a net external force. The bike decelerates; the rider’s torso, having forward momentum, tends to continue forward relative to the slowing frame, causing a forward bend.



Step-by-Step Solution:
Bicycle decelerates quickly.Rider’s center of mass continues forward ⇒ apparent forward pitch.Hands/arms on handlebar create a pivot, accentuating the forward bend.



Verification / Alternative check:
In practice, protective technique (shifting hips back, bracing arms) reduces observable bending. Perfectly balanced braking or mild braking can minimize the effect; still, in ordinary sudden stops, forward bend is common.



Why Other Options Are Wrong:
Always: too strong—skilled riders or specific conditions can avoid visible bending. Never: contradicts basic mechanics. Sometimes vs Generally: “Generally” fits typical outcomes across ordinary conditions.



Common Pitfalls:
Ignoring rider technique and brake distribution (front vs rear). Overgeneralizing to “always.”



Final Answer:
Generally

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