Answer:
a.
b.Attractive
Explanation:
We are given that


Mass of an electron,
Mass of proton,
Distance between electron and proton,R=

a.Substitute the values then we get


b.We know that like charges repel to each other and unlike charges attract to each other.
Proton and electron are unlike charges therefore, the force between proton and electron is attractive.
Answer:
Doppler effect changes the wavelength of the light emitted, depending upon whether source is moving away or coming towards the observer(detector).
Explanation:
Doppler effect in light is actually a relativistic effect but somewhat similar to the one which happens in sound waves.
When the source is moving away from the detector, the wavelength of the light emitted from the source appears to be increased as seen by the detector, as a result the frequency decreases(we know that frequency of light= speed of light/wavelength of light. Here speed of light is constant and frequency of light is inversely proportional to its wavelength)
Due to this decrease in frequency the light emitted from the source appears more red, since red color is on low frequency side in the electromagnetic spectrum.
Similarly for the source moving towards the detector, the wavelength appears to be decreased, thereby resulting in increase in frequency and the source appears blue. The shift in frequency is known as doppler shift.
The shift in frequency when the source is moving away is known as redshift and the one where the source is moving towards detector is known as blueshift
Answer:
A. how dose each model effect the temperature of a substance
Explanation:
The masses of both objects and the distance between their centers.
Im sure there are others but i know that bugs existed as long as the earth has