Answer:
4 times greater
Explanation:
<u>Step 1:</u> Calculate light-collecting area of a 20-meter telescope (A₁) by using area of a circle.
Area of circle = π*r² =
Where d is the diameter of the circle = 20-m


A₁ = 314.2 m²
<u>Step 2:</u> Calculate light-collecting area of a 10-meter Keck telescope (A₂)

Where d is the diameter of the circle = 10-m

A₂ = 78.55 m²
<u>Step 3</u>: divide A₁ by A₂

= 4
Therefor, the 20-meter telescope light-collecting area would be 4 times greater than that of the 10-meter Keck telescope.
Density <em>ρ</em> is mass <em>m</em> per unit volume <em>v</em>, or
<em>ρ</em> = <em>m</em> / <em>v</em>
Solving for <em>v</em> gives
<em>v</em> = <em>m</em> / <em>ρ</em>
So the given object has a volume of
<em>v</em> = (130 g) / (65 g/cm³) = 2 cm³
you are so wise how do you do it?
1.Epithelium- lines and covers surfaces
2. Connective tissue- protect, support, and bind together
3. Muscular tissue- produces movement
4. Nervous tissue- receive stimuli and conduct impulses
Hope i helped u :)
A velocity and wavelength
Explanation:
When a periodic wave travels from one medium to another, its velocity and wavelength changes in the process.
A periodic wave is a wave with repeating pattern.
- When a wave crosses different medium with different densities, their velocity and wavelength changes.
- This implies that wave causes disturbances in different ways.
- This change in wavelength and velocity as a wave crosses two medium is known as refraction.
- When a wave moves from a less dense medium to a denser one, the velocity reduces and the wavelength increases.
learn more:
Refraction brainly.com/question/12370040
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