Why do apples fall straight down, not sideways?
Equivalence principle
Why do apples fall straight down, not sideways?
Imagine you're in a car on a straight road, and suddenly it starts accelerating. You feel pushed back into your seat. Why does this happen?
It's because of the way gravity and acceleration are connected. In your car, the acceleration makes you feel heavier, just like gravity pulls you down on Earth.
Example
If the car accelerates at 5 m/s², and you weigh 70 kg, you feel like you weigh 175 kg (70 kg + 105 kg from acceleration).
Remember this
This feeling is due to the equivalence of inertial and gravitational mass, showing they behave similarly under acceleration.
Text adapted from Wikipedia, licensed under CC BY-SA 4.0.
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