Question

1 according to newtons first law of motion, which of the following objects will change its motion? a a bike rider on a smooth and level road, pedaling at a constant rate b a ball rolling across the floor that bumps into another object c a train pulling on another train, each with the same amount of force d a chair sitting on the floor with balanced forces acting in opposite directions

Explanation:

Newton's first law of motion states that an object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.

• Option A: The bike rider has balanced forces (pedaling force counteracts friction), so motion doesn't change.
• Option B: When the ball bumps into another object, an unbalanced force acts on it, changing its motion.
• Option C: Equal forces in opposite directions (balanced forces) mean no change in motion.
• Option D: Balanced forces acting on the chair mean no change in motion.

Answer:

B. A ball rolling across the floor that bumps into another object