Answer:
Explanation:
Newton's first law of motion:
An object in motion stays in motion, and an object at rest stays at rest, until acted upon by an unbalanced force.
Newton's second law:
The net force on an object is equal to its mass times its acceleration.
Newton's third law:
For every action, there is an opposite and equal reaction.
Answer:
Because the Moon casts a smaller shadow than Earth does, eclipses of the Sun tightly constrain where you can see them. If the Moon completely hides the Sun, even for a moment, the eclipse is considered total.
Explanation:
Answer:
D. because the light is reflected back into the fiber along its sides
Explanation:
The fiber is constructed in a way that the light is bent/reflected/refracted toward the center core of glass. So, from the center core, there is a layer above it that has a different propagation than the core, and above that the same thing. To give you a real world visual example, if you look down in a pool of water, then stick a straight stick into it, you see that the straight stick appears to bend. That is what is happening to the light as it travels through a different medium (air to water). This same effect is incorporated in the fiber optic cable construction.
Answer:
mgh₁ + ½mv₁² = mgh₂ + ½mv₂²
Explanation:
Initial total energy = final total energy
PE₁ + KE₁ = PE₂ + KE₂
mgh₁ + ½mv₁² = mgh₂ + ½mv₂²
