Before beginning an exercise program a person should always

Why do we use the hydrogen spectrum to identify if a star is red or blue<br> shifted? *

Lady_Fox [76]

Answer:

But if you place a clear container filled with hydrogen gas between the flashlight and the prism, gaps appear in the smooth rainbow of colors, places where the light literally goes missing. The dark absorption lines of a star at rest (left) get shifted towards red if the star is moving away from Earth (right)

Explanation:

6 0

2 years ago

A motorcycle and a police car are moving toward one another. The police car emits sound with a frequency of 523 Hz and has a spe

Firdavs [7]

To solve this problem it is necessary to apply the concepts related to Dopler's Law. Dopler describes the change in frequency of a wave in relation to that of an observer who is in motion relative to the Source of the Wave.

It can be described as

$f = \frac{c\pm v_r}{c\pm v_s}f_0$

c = Propagation speed of waves in the medium

$v_r$ = Speed of the receiver relative to the medium

$v_s$ = Speed of the source relative to the medium

$f_0 =$ Frequency emited by the source

The sign depends on whether the receiver or the source approach or move away from each other.

Our values are given by,

$v_s = 32.2m/s \rightarrow$ Velocity of car

$v_r = 14.8 m/s \rightarrow$ velocity of motor

$c = 343m/s \rightarrow$ Velocity of sound

$f_0 = 523Hz \rightarrow$ Frequency emited by the source

Replacing we have that

$f = \frac{c + v_r}{c - v_s}f_0$

$f = \frac{343 + 14.8}{343 - 32}(523)$

$f = 601.7Hz$

Therefore the frequency that hear the motorcyclist is 601.7Hz

8 0

3 years ago

A transformer has a secondary voltage of 140 volts and a secondary current of 3.5 amps. if the primary current is 10 amps, what

Lynna [10]

For an ideal transformer power loss is assumed to be zero

i.e. the power in primary coil due to input voltage must be equal to power in secondary coil due to output voltage

this can be written in form of equation

$V_1 i_1 = V_2 i_2$

here we know that

$V_2 = 140 volts$

$i_2 = 3.5 A$

$i_1 = 10 A{/tex]now we will use above equation[tex]140*3.5 = 10 * V_1$

$V_1 = 49 volts$

So primary coil voltage is 49 Volts

7 0

2 years ago

Clouds, wind, and rain are part of the _____.

Musya8 [376]

A its Stratosphere, Sorry I didn't see your answer, its bilogy I think not physics.. :)

8 0

2 years ago

The width of the central maxima, formed from light of wavelength 575 nm behind a single slit that has a width of 115 μm, is 1.15

Lady bird [3.3K]

Answer:

L = 1.15 m

Explanation:

The diffraction phenomenon is described by the equation

a sin θ = m λ

Where a is the width of the slit, λ the wavelength and m is an integer, the order of diffraction is left.

The diffraction measurements are made on a screen that is far from the slit, and the angles in the experiment are very small, let's use trigonometry

tan θ = y / L

tan θ = sint θ / cos θ≈ sin θ

We substitute in the first equation

a (y / L) = m λ

The first maximum occurs for m = 1

The distance is measured from the center point of maximum, which coincides with the center of the slit, in this case the distance is the total width of the central maximum, so the distance (y) measured from the center is

y = 1.15 / 2 = 0.575 cm

y = 0.575 10⁻² m

Let's clear the distance to the screen (L)

L = a y / λ

Let's calculate

L = 115 10⁻⁶ 0.575 10⁻² / 575 10⁻⁹

L = 1.15 m

3 0

2 years ago