Here's a formula that's simple and useful, and if you're really in
high school physics, I'd be surprised if you haven't see it before.
This one is so simple and useful that I'd suggest memorizing it,
so it's always in your toolbox.
This formula tells how far an object travels in how much time,
when it's accelerating:
Distance = (1/2 acceleration) x (Time²).
D = 1/2 A T²
For your student who dropped an object out of the window,
Distance = 19.6 m
Acceleration = gravity = 9.8 m/s²
D = 1/2 G T²
19.6 = 4.9 T²
Divide each side by 4.9 : 4 = T²
Square root each side: 2 = T
When an object is dropped in Earth gravity,
it takes 2 seconds to fall the first 19.6 meters.
1) use energy from food
2) get rid of wastes
3) maintain
Answer:

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Explanation:
From the exercise we know two information. The real speed and the experimental measured by the speedometer

Since the speedometer is only accurate to within 0.1km/h the experimental speed is

Knowing that we can calculate Kinetic energy for the real and experimental speed


Now, the potential error in her calculated kinetic energy is:

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