The answer is electric current
<span>The formula for frequency is speed of light divided by wavelength. 650 nm represents the wavelength and 3x10^8 m/s is the speed of light. If you convert 650nm to meters you get 6.5x10^-7 m so you can divide using the formula above, giving you 4.6x10^14 1/s or Hz, the unit of frequency in Physics.</span>
Explanation:
Particles in solids are always vibrating (moving back and forth) in place.
Hey there! :D
We want to find an answer choice that is reversible. If the physical change could have some way of being fixed, then it is a physical change. If it is a chemical change, the make-up is different and there is no way that it could change.
A cookie baking cannot be reversed. Cookies cannot go back to being cookie dough.
Paper burning cannot be reversed. Ashes and smoke cannot go back to being paper.
However, if your ice cream melts, you can refreeze it. Therefore, "3" is the best answer to the question.
I hope this helps!
~kaikers