Question

A narrow beam of protons produces a current of 1.6 × 10^–3 A. There are 10^9 protons in each meter along the beam.

Answer 1

A narrow beam of protons produces a current of 1.6 × 10–3 A. There are 109 protons in each meter along the beam. Of the following, which is the best estimate of the average speed of the protons in the beam?

Answer 2

By executing dimensional analysis:

1.6 × 10–3 A = 1.6 × 10–3 C/s ÷ 1.6 × 10–19 C/proton = 1016 protons/sec ÷ 109 protons/meter = 107m/s.

So, option D is the correct Answer.dimensional analysis is a phenomenon related to engineering calculation, the analysis of the interrelated dimension matching between different physical quantities, by means of identifying their base quantities like length, mass, time, as well as electric charge and units of measurement like miles vs. kilometres, or pounds vs. kilograms and tracking these dimensions.