Answer:
cell pohnes convert sound waves into radio waves
electromagnetic waves used in cellphone communications are called: radio waves
To send out a radio signal far and wide.. it is called: broadcast
Explanation:
Answer:
doppler shift's formula for source and receiver moving away from each other:
<em>λ'=λ°√(1+β/1-β)</em>
Explanation:
acceleration of spaceship=α=29.4m/s²
wavelength of sodium lamp=λ°=589nm
as the spaceship is moving away from earth so wavelength of earth should increase w.r.t increasing speed until it vanishes at λ'=700nm
using doppler shift's formula:
<em>λ'=λ°√(1+β/1-β)</em>
putting the values:
700nm=589nm√(1+β/1-β)
after simplifying:
<em>β=0.17</em>
by this we can say that speed at that time is: v=0.17c
to calculate velocity at an acceleration of a=29.4m/s²
we suppose that spaceship started from rest so,
<em>v=v₀+at</em>
where v₀=0
so<em> v=at</em>
as we want to calculate t so:-
<em>t=v/a</em> v=0.17c ,c=3x10⁸ ,a=29.4m/s²
putting values:
=0.17(3x10⁸m/s)/29.4m/s²
<em>t=1.73x10⁶</em>
Answer: 7.5 rev/s
Explanation:
We are given the angular velocity
a helicopter's main rotor blades:

However, we are asked to express this
in the International Systrm (SI) units. In this sense, the SI unit for time is second (
):


In this question force is measured in g cm/s2 so we know that to get the answer we times g by cm/s2
50 × 20 = 1000
Answer:
the answer is a time your welcome