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Answer: electrons sometimes behave like waves
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The French physicist <em>Louis De Broglie</em> proposed the existence of matter waves, that is to say that <em>all matter has a wave associated with it</em>.
On the other hand, <em>Heisenberg</em> enunciated the uncertainty principle, which postulates that the fact that each particle has a wave associated with it, imposes restrictions on the ability to determine its position and speed at the same time.
These postulations were tested with the double slit experiment (<u>formerly applied to photons</u>) applied to electrons, and the result was: electrons (as well as the other particles different from the photons) are able to behave as waves.
Answer: V = 15 m/s
Explanation:
As stationary speed gun emits a microwave beam at 2.10*10^10Hz. It reflects off a car and returns 1030 Hz higher. The observed frequency the car will be experiencing will be addition of the two frequency. That is,
F = 2.1 × 10^10 + 1030 = 2.100000103×10^10Hz
Using doppler effect formula
F = C/ ( C - V) × f
Where
F = observed frequency
f = source frequency
C = speed of light = 3×10^8
V = speed of the car
Substitute all the parameters into the formula
2.100000103×10^10 = 3×10^8/(3×10^8 -V) × 2.1×10^10
2.100000103×10^10/2.1×10^10 = 3×108/(3×10^8 - V)
1.000000049 = 3×10^8/(3×10^8 - V)
Cross multiply
300000014.7 - 1.000000049V = 3×10^8
Collect the like terms
1.000000049V = 14.71429
Make V the subject of formula
V = 14.71429/1.000000049
V = 14.7 m/s
The speed of the car is 15 m/s approximately