If the soloist produces "x" decibels and the 10-person choir produces "y" decibels, combined they will produce "x+y" decibels.
The second choir has 90 additional singers, we base our description on the first choir. If a 10-person choir produces "x+y" decibels, then the 90 person choir produces 10 (x+y) decibels.
Answer:
the kinetic energy lost due to friction is 22.5 J
Explanation:
Given;
mass of the block, m = 0.2 kg
initial velocity of the block, u = 25 m/s
final velocity of the block, v = 20 m/s
The kinetic energy lost due to friction is calculated as;

Therefore, the kinetic energy lost due to friction is 22.5 J
C.
Explanation: Because mirrors are lighter, and they are easier than lenses to make perfectly smooth.
Space telescopes must be placed in orbit around earth in order to observe short-wavelength radiation.
<h3>What is telescope?</h3>
A telescope is an optical instrument that uses lenses, curved mirrors, or a combination of both to watch distant objects.
When atoms in a gas reach this temperature, they travel so quickly that when they collide, they release X-ray photons with wavelengths smaller than 10 nanometers.
Because the Earth's atmosphere prevents all X-rays from space, these wavelengths must be seen using space telescopes.
To study short-wavelength radiation, space telescopes must be put in orbit around the Earth.
Hence, space telescope is the correct answer.
To learn more about the telescope, refer:
brainly.com/question/556195
#SPJ1
Answer:
Fundamental quantities are the base quantities of a unit system, and they are defined independent of the other...
• Derived quantities are based on fundamental quantities, and they can be given in terms of fundamental quantities.
• In SI units, derived units are often given names of people such as Newton and Joule.
Explanation: