Bennett Mechanical Test Velocity and Gravity 3 — Questions and Answers
Question 1: Why does a feather fall slower than a rock in normal air?
- Gravity is weaker on the feather
- Air resistance affects the feather more (Correct answer)
- The feather has less mass attraction
- The rock is denser so gravity is stronger
Correct answer: Air resistance affects the feather more
Air resistance has a greater slowing effect on the light, large-surface feather.
Question 2: A rock falls for 2 seconds. About how far does it travel (ignoring air resistance)?
- About 5 meters
- About 10 meters
- About 20 meters (Correct answer)
- About 40 meters
Correct answer: About 20 meters
Distance equals ½gt², so ½ × 10 × 2² ≈ 20 meters.
Question 3: On the Moon, where gravity is about 1/6 of Earth's, a dropped object will fall how compared to Earth?
- Faster
- Slower (Correct answer)
- At the same rate
- It will not fall
Correct answer: Slower
Weaker lunar gravity means a slower acceleration, so the object falls more slowly.
Question 4: An object moving at constant velocity has what acceleration?
- Zero (Correct answer)
- Positive
- Negative
- Equal to gravity
Correct answer: Zero
Constant velocity means no change in speed or direction, so acceleration is zero.
Question 5: Which has greater velocity: a 10 kg ball at 5 m/s or a 2 kg ball at 5 m/s?
- The 10 kg ball
- The 2 kg ball
- They have equal velocity (Correct answer)
- Cannot be determined
Correct answer: They have equal velocity
Velocity depends only on speed and direction, not mass, so both are equal.
Question 6: A projectile launched horizontally and a ball dropped at the same instant will land when?
- The dropped ball lands first
- The projectile lands first
- They land at the same time (Correct answer)
- Neither lands
Correct answer: They land at the same time
Horizontal motion does not affect vertical fall, so both hit the ground simultaneously.
Question 7: What happens to the velocity of a falling object as it continues to fall (ignoring air resistance)?
- It stays constant
- It increases steadily (Correct answer)
- It decreases steadily
- It becomes zero
Correct answer: It increases steadily
Gravity continuously accelerates the object, so its velocity increases over time.
Bennett Mechanical Test Velocity and Gravity 3
Why does a feather fall slower than a rock in normal air?