Answer:
The measurement which is the most precise is 104.6 °C.
Explanation:
The measurement which is most precise must be very close to the actual value of the temperature.
Thus, the unit which have less value of the |Δx| (error) must be most precise.
Thus,
Actual value = 105.1 °C
Value = 103.7 °C
<u>|Δx| = 1.4 °C</u>
Value = 108.4 °C
<u>|Δx| = 3.3 °C</u>
Value = 105.8 °C
<u>|Δx| = 0.7 °C</u>
Value = 104.6 °C
<u>|Δx| = 0.5 °C</u>
<u>Thus, The measurement which is the most precise is 104.6 °C.</u>
To calculate the speed and velocity of the Ann`s we use the formula,
Here, d is distance and t is time and v if we take it with direction then it is called velocity and if we take it without the direction then it is called speed.
Given 
and 
.
Substituting these values in above equation we get
As Ann walked towards south direction therefore, Ann`s velocity is 3 mi/h south and her speed is 3 mi/h .
The force pushing down is the force of Gravity. On a chair it is in perfect balance with the force pushing up (the normal force)
in terms of magnitude
FN = FG = mg
the forces are in opposite direction
hope this helps
Answer:
red shift, indicating that the universe is expanding
Explanation:
Doppler effect occurs when a source of a wave (e.g. light, or sound waves) moves relative to an observer; as a result of this relative motion, the wavelength of the wave appears lengthened/shortened to the observer. Two situations can occur:
- The source of the wave is moving towards the observer - in this case, the wavelength of the wave becomes shorter. If the wave is visible light, such as the light emitted by distant galaxies, this means that the wavelength of the light shifts towards the blue-end of the spectrum (blue-shift)
- The source of the wave is moving away from the observer - in this case, the wavelength of the wave becomes longer. If the wave is visible light, such as the light emitted by distant galaxies, this means that the wavelength of the light shifts towards the red-end of the spectrum (red-shift)
In our universe, we observe a red-shift for all the distant galaxies: this means that these galaxies are moving away from us, so this is an indication that the universe is expanding.
