How to Run on the Moon

When the elevator is stopped, the 2 forces are adjacent and opposite, and the nett unit is zero. But if you're accelerating upward, the nett unit indispensable besides beryllium upward. This means the mean unit exceeds the gravitational unit (shown by the lengths of the 2 arrows above). So you feel heavier erstwhile the mean unit increases. We tin telephone the mean unit your “apparent weight.”

Get it? You're successful this container and it looks similar nothing's changing, but you consciousness yourself being pulled downward by stronger gravity. That's due to the fact that your frame of reference, the seemingly motionless elevator car, is successful information zooming upward. Basically, we're shifting from however you spot it wrong the strategy to however idiosyncratic outside the strategy sees it.

Could you physique an elevator connected the satellite and person it accelerate accelerated capable to regain your earthly weight? Theoretically, yeah. This is what Einstein's equivalence rule states: There is nary quality betwixt a gravitational tract and an accelerating notation frame.

A Roundabout Solution

But you spot the problem: To support accelerating upward for adjacent a fewer minutes, the elevator shaft would person to beryllium absurdly tall, and you'd soon scope arsenic ridiculous speeds. But wait! There's different mode to nutrient an acceleration: determination successful a circle.

Here's a physics riddle for you: What are the 3 controls successful a car that marque it accelerate? Answer: the state pedal (to velocity up), the brake (to dilatory down), and the steering instrumentality (to alteration direction). Yes, each of these are accelerations!

Remember, acceleration is the complaint of alteration of velocity, and here's the cardinal thing: Velocity successful physics is simply a vector. It has a magnitude, which we telephone its speed, but it besides has a circumstantial direction. Turn the car and you're accelerating, adjacent if your velocity is unchanged.

So what if you conscionable drove successful a circle? Then you'd beryllium perpetually accelerating without going anywhere. This is called centripetal acceleration (a_c), which means center-pointing: An entity moving successful a ellipse is accelerating toward the center, and the magnitude of this acceleration depends connected the velocity (v) and the radius (R):