"A machine can decrease either the input force or the input distance needed to do a given amount of work" is the best statement that describes why a machine is useful.
Answer: Option D
<u>Explanation
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A machine is simply defined as a device that helps humans, helping them to transfer the required amount of force to compete any task, changing the direction of motion, increasing the magnitude of force to complete any task, reduce the time or distance needed to cover while performing any task.
Machines can be simple mechanical device or a combination of multiple mechanical or technical devices to reduce the amount of input force or increase the output.
I believe the answer is B.
Answer:
Physical change because even though gas formation was observed, the water was undergoing a state change, which means that its original properties are preserved.
Explanation:
The gas formation seen is in fact the transition of the liquid water to a gas state, not the formation of a new gas.
Those waves carry an amount of energy that can be measured. The energy in a wave is determined by two variables. One is amplitude, which is the distance from the rest position of a wave to the top or bottom. Large amplitude waves contain more energy. Wave A has a greater intensity and transfers more energy. Wave B has a greater intensity and transfers more energy. Waves that require matter to transfer energy are mechanical waves. The matter through which a mechanical wave travels is called a medium. A mechanical wave travels as energy is transferred from particle to particle in the medium. There are two kinds of mechanical waves. The greater the waves amplitude the greater the waves energy. ... A wavelength will travel only as long as it has energy to carry. Gamma rays
Gamma rays have the highest energies, the shortest wavelengths, and the highest frequencies. Radio waves, on the other hand, have the lowest energies, longest wavelengths, and lowest frequencies of any type of EM radiation. Electromagnetic waves cause oscillations in electrical and magnetic fields. It is important to remember that all waves transfer energy but they do not transfer matter . For example, if a ball is placed on the surface of a pond when ripples move across it, the ball will move up and down but not outwards with the wave.