B. The farthest point in the Moon's orbit to Earth
C. The closest point in Earth's orbit of the Sun
D. The Sun's orbit that is closest to the Moon
Answer:
A. The closest point in the Moon's orbit to Earth
Explanation:
The perigee is defined as the closest point in the orbit of an object (such as a satellite) from the centre of the Earth. In this case, the Earth's satellite is the Moon, so the perigee is defined as the closest point in the Moon's orbit to Earth. so option A is the correct one.
Let's see instead the names of the other options:
B. The farthest point in the Moon's orbit to Earth --> this point is called apogee
C. The closest point in Earth's orbit of the Sun --> this point is called perihelion
D. The Sun's orbit that is closest to the Moon --> this point has no specific name
b. increased risk of lung cancer
c. change in senses
d. increased risk of cardiovascular disease
In what year were cigarette packages made to include 6 warning labels that mentioned the surgeon general
All of the following are long-term risks associated with exposure to secondhand smoke EXCEPT:
A. increased risk of respiratory illness
B. increased risk of lung cancer
C. change in senses
D. increased risk of cardiovascular disease
This is the Correct Answer.
B. Sample A would be best, because the percentage of the energy in an incident wave that remains in a reflected wave from this material is the largest.
C. Sample C would be best, because the percentage of the energy in an incident wave that remains in a reflected wave from this material is the smallest.
D. Sample C would be best, because the percentage of the energy in an incident wave that remains in a reflected wave from this material is the largest.
Answer: Option C: Sample C would be best, because the percentage of the energy in an incident wave that remains in a reflected wave from this material is the smallest.
Explanation:
The absorption coefficient of the samples is given. Sample A has 30%, Sample B has 47% and Sample C has 62%. This means that sample C absorbs the most percentage of energy incident on it. The energy in the reflected wave would be least. Hence, it would be best to use for a room to make it soundproof.
The correct answer is Option C) Sample C would be best, because the percentage of the energy in an incident wave that remains in a reflected wave from this material is the smallest.
As the coefficient of absorption would define the energy present in the reflected wave, the material C has the highest percentage of absorption i.e. 62% and would be best suitable to make a sound proof room.
both vacuums and mediums
mediums only
mediums only, mechanical waves always propagate through medium