Two stones of very different mass are released from the same height with air resistance ignored. Which one reaches the ground first?
ABoth reach at the same time
BThe heavier one arrives first
CThe lighter one arrives first
DThe wider one arrives first
Answer & Solution
Correct answer: A. Both reach at the same time
1. The gravitational force on a stone is larger when the stone has a larger mass.
2. Newton's second law says acceleration equals the resultant force divided by the mass.
3. Putting the gravitational force into that expression makes the mass cancel out.
4. The acceleration due to the Earth's gravity therefore does not depend on the mass of the body.
5. Both stones fall with the same gravitational acceleration and land together.
6. Expecting the heavier stone to win is the trap, because a bigger force on a bigger mass gives the same acceleration.
_Source: Siyavula Physical Sciences Grade 11 (Everything Science, CC BY 4.0), Chapter 2: Newton's laws_
Related questions
According to Newton's law of universal gravitation, the force between two point masses depWhich statement is true of the two forces in a Newton's third law action-reaction pair?A fly hits the windscreen of a moving car. Compared with the force the fly exerts on the wA person stands on a bathroom scale inside a lift. The lift begins to accelerate downwardsA lift hangs on a cable and moves upwards at a constant velocity. What is the resultant foIn Newton's second law, how is the acceleration of a body related to its mass?What name is given to the property that makes an object keep doing what it is already doinNo unbalanced force acts on a moving trolley. According to Newton's first law, what does t