Question

The solar wind consists of protons from the Sun moving toward Earth (the wind actually consists of about 95% protons). The number density of protons at a distance from the Sun equal to the orbital radius of Earth is about 7.0 protons per cubic centimeter. Your research team monitors a satellite that is in orbit around the Sun at a distance from the Sun equal to Earth's orbital radius. You are in charge of the satellite's mass spectrometer, an instrument used to measure the composition and intensity of the solar wind. The aperture of your spectrometer is a circle of radius 28.4 cm. The rate of collection of protons by the spectrometer is such that they constitute a measured current of 91.0 nA. What is the speed of the protons in the solar wind

Answer 1

`\mathbf{V_d = 3.2 * 10^5 \ m/s}`

Step-by-step explanation:

`\text{The speed of the protons can be estimated by using the formula:}`

`V_d = (I)/(enA)`

`where;`

`\text{e = proton charge}`

`\text{n = No. of protons per unit volume}`

`\text{A = area of aperture}`

`V_d = (91 * 10^(-9) \ A)/((1.602 * 10^(-19) \ C (7.0 * 10^6 \ m^(-3) ) (\pi) (0.284 \ m)^2)`

`\mathbf{V_d = 3.2 * 10^5 \ m/s}`