If your speed changes from 10 km/h to 6 km/h then
you have an acceleration.
Whether it's a positive or negative one completely depends
on which direction you decided to call the positive direction,
when you started considering your speed and its changes.
If you decided to call the direction in which you're traveling
the positive direction, then a decrease in your speed is a
negative acceleration.
But you could just as easily have said that you're traveling
in the negative direction. If you did that, then a decrease in
your speed would be a positive acceleration.
It's completely up to you, and how you define things.
The electromagnetic spectrum is the system of frequencies that show electromagnetic radiation, respective wavelengths, and photon energies. Some examples of frequencies found on the electromagnetic spectrum are radio waves, microwaves, infrared, optical, ultraviolet, X-rays, and gamma-rays.
Answer:
Both
Explanation:
The lithosphere is part of both the crust and the mantle.
It is the surface layer of the earth and also the most rigid layer. It is formed by the crust and the outermost part of the mantle. It is divided into two types: continental lithosphere and oceanic lithosphere.
The oceanic lithosphere has an approximate thickness of 50 - 100km, and the continental olithosphere of 40 - 200km.
