Why doesn’t a raindrop accelerate as it approaches the ground?

A
Gravity pulls it down at a constant rate.

B
Air resistance counteracts the gravitational force.

C
Its mass decreases, decreasing its speed.

D
Objects in motion decelerate over distance.

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Question

A skydiver jumps from a plane. After several seconds, she stops speeding up and falls at a constant speed. Explain the forces acting on her at this moment.

Answer

The downward force of gravity (weight) is perfectly balanced by the upward force of air resistance (drag). The net force is zero, so according to Newton's First Law, she continues at a constant velocity (terminal velocity).

Question

Two balls of identical size but different mass (e.g., a steel ball and a plastic ball) are dropped from a great height in air. Which one will have a higher terminal velocity, and why?

Answer

The steel ball will have a higher terminal velocity. Terminal velocity is reached when drag force equals weight. Heavier objects have greater weight, requiring a higher speed to produce enough drag force to balance it.

Question

Compare the fall of a feather and a rock in a vacuum chamber versus in normal air. Why is the difference dramatic in air but not in a vacuum?

Answer

In a vacuum, there is no air resistance, so both objects accelerate downward at *g* and hit the ground simultaneously (if dropped from the same height). In air, the large surface area of the feather creates significant drag at low speeds, causing it to reach a very low terminal velocity almost immediately, while the rock's higher mass-to-area ratio allows it to accelerate to a much higher terminal velocity.

Question

Draw a simple free-body diagram for a falling object that has just reached its terminal velocity. Label the forces.

Answer

The diagram should show two force arrows of equal length acting on a dot. One arrow points downward labeled "Weight (F_gravity)". The other arrow points upward labeled "Air Resistance / Drag (F_drag)". The arrows are equal in length, indicating a net force of zero.

Question

Describe what the velocity-time graph looks like for an object dropped from rest in air, as it falls toward the ground.

Answer

The graph starts with a positive, increasing slope (acceleration). The slope gradually decreases as speed increases and drag builds. The line eventually becomes horizontal (slope = 0), indicating constant terminal velocity with zero acceleration.

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Does an object's mass directly determine its terminal velocity in air?

Why doesn’t a raindrop accelerate as it approaches the ground?

A
Gravity pulls it down at a constant rate.

B
Air resistance counteracts the gravitational force.

C
Its mass decreases, decreasing its speed.

D
Objects in motion decelerate over distance.

A raindrop does not accelerate as it approaches the ground because air resistance counteracts the gravitational force.

Topic Flashcards

Mini Quiz

Related Questions

Why doesn’t a raindrop accelerate as it approaches the ground?

A Gravity pulls it down at a constant rate. B Air resistance counteracts the gravitational force. C Its mass decreases, decreasing its speed. D Objects in motion decelerate over distance.

A raindrop does not accelerate as it approaches the ground because air resistance counteracts the gravitational force.

Topic Flashcards

Mini Quiz

Related Questions

A
Gravity pulls it down at a constant rate.

B
Air resistance counteracts the gravitational force.

C
Its mass decreases, decreasing its speed.

D
Objects in motion decelerate over distance.