Answer:
Speed of physicist car is 0.036c or 1.08 x 10⁷ m/s .
Explanation:
Doppler Effect is defined as the change in frequency or wavelength of the wave as the source or/and observer moving away or towards each other.
In this case, the Doppler effect equation in terms of wavelength is :
......(1)
Here 
is source wavelength, 
is observed wavelength, v is speed of the observer and c is the speed of light.
Given :
Source wavelength, = 660 nm = 660 x 10⁻⁹ m
Observed wavelength, 
= 555 nm = 555 x 10⁻⁹ m
Substitute these values in the equation (1).
v = 1.08 x 10⁷ m/s
Answer:
B
Explanation:
because, convection is the transfer of heat between fluid substances/materials
Answer:
D. Top is emission; bottom absorption.
Explanation:
Emission and spectrum of elements are due to the element absorbing or emitting wavelength of e-m energy. Elementary particles of elements can absorb energy from a ground state to enter an excited state, creating an absorption spectrum, or they can lose energy and fall back to a lower energy state, creating an emission spectrum. A simple rule to differentiate between an emission and an absorption spectrum is that: "all absorbed wavelength is emitted, but not all emitted wavelength is absorbed."
From the image, the lines indicates wavelengths. We can see that all of the wavelengths of the bottom absorption spectrum coincides with some of the wavelength of the upper emission wavelengths.
Sound waves travel around the boxed room causing them to bounce off the nearest walls to the end of the room
