MY personal interpretation of nothing is no atoms or particles of anything. but keep in mind im 11 <span />
Answer:

Explanation:
When a spring is compressed, the force exerted by the spring is given by:

where
k is the spring constant
x is the compression of the spring
In this problem we have:
k = 52 N/m is the spring constant
x = 43 cm = 0.43 m is the compression
Therefore, the force exerted by the spring on the dart is

Now we can apply Newton' second law of motion to calculate the acceleration of the dart:

where
F = 22.4 N is the force exerted on the dart by the spring
m = 75 g = 0.075 kg is the mass of the dart
a is its acceleration
Solving for a,

If the measurement is in joules then you can push something or pull something as long as you are moving the object. Formula: f*n force times newtons
This question is a very good one indeed! I am very happy you asked it. I would first like to say that, although energy is important, our planet is more so. That is why I feel like we should always try to explore ideas that are both useful to the human race but also useful in protecting our environment because what is the use in having energy if we will not be able to use it. That is why I feel that we should try at types of energy like solar and wind. The problem is finding ways that are less expensive and more efficient. For example, creating a wind energy system that creates a sizeable about of energy and also is not too expensive and hard to make like the wind turbines of nowadays. Also what comes into question is the effect of these ideas and I feel that although some of these may have harmful effects, they must be used. One thing though is that I do not agree in expanding on our oil and gas exploration because it has so many bad effects to our environment that it is hardly worth it. If we can find alternatives in these other sources, like many states in the USA are trying to do, then we will be able to move much faster in technology and also help protect our lovely planet.
Answer:
Solar water heaters are devices that use energy from the sun to heat water. ... This metal surface, placed in contact with the water, will heat the water. Black-painted surfaces that receive the sun's heat become hotter than surfaces of any other color. The black metal plate is called a collector.