A sound wave<span> in a steel rail </span>has<span> a </span>frequency of<span> 620 </span>Hz<span> and a </span>wavelength<span> of 10.5 ... Find the </span>speed<span> of </span>a wave<span> with a </span>wavelength of 5<span> m and a </span>frequency of<span> 68 </span>Hz<span>.</span>
Answer: Physical changes in nature could then be erosion in a mountain, the melting of snow, and a river freezing over from the cold. Since none of these changes affect the chemical composition of the mountain, the snow, or the river, they are physical changes.
Explanation:
Intrusive igneous rocks cool down from magma slowly because they form underneath the surface, that will make them have large crystals.
Extrusive igneous rocks cool down from lava rapidly because they form at the surface, so that will make them have small crystals.
Answer:
A
Explanation:
Begin as protostars, which fire up when they collapse and become denser and hotter.
Answer:
The coin is less dense than the water thefore it can float.
Explanation: