Answer:
Democritus had no scientific instruments to extend the reach of his senses, so all of his experiments were just 'mind experiments', but because Democritus was a philosopher, he thought more into depth about why we humans are alive which led to the atomic theory.
Explanation:
As long as it sits on the shelf, its potential energy
relative to the floor is . . .
Potential energy = (mass) x (gravity) x (height) =
(3 kg) x (9.8 m/s²) x (0.8m) = <u>23.52 joules</u> .
If it falls from the shelf and lands on the floor, then it has exactly that
same amount of energy when it hits the floor, only now the 23.52 joules
has changed to kinetic energy.
Kinetic energy = (1/2) x (mass) x (speed)²
23.52 joules = (1/2) x (3 kg) x (speed)²
Divide each side by 1.5 kg : 23.52 m²/s² = speed²
Take the square root of each side: speed = √(23.52 m²/s²) = <em>4.85 m/s </em> (rounded)
I am not so sure about this it is too difficult
Answer: The gravitational
Explanation: The student is pushing the box so u have to have gravitational force so it could move
The new acceleration is 
Explanation:
We can answer this problem by applying Newton's second law, which states that:

where
F is the net force on an object
m is the mass of the object
a is its acceleration
The equation can be rewritten as

In this problem, the initial acceleration is

Later:
- The net force is tripled: 
- The mass is halved: 
Therefore, the new acceleration is:

which means that the new acceleration is 6 times the original acceleration, therefore

Learn more about acceleration:
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