Consider a line of positive charge with line charge density ? as measured in a frame S at rest with respect to the charges.(a) Show that the electric field a distance r from this charged line has magnitude E = ?/2??₀r, and that there?s no magnetic field (no relativity needed here). Now consider the situation in a frame S? moving at speed v parallel to the line of charge.(b) Show that the charge density measured in S? is given by ?? = ??, where ?(c) Use the result of (b) to find the electric field in S?. Since the charge is moving with respect to S?, there?s a current in S?.(d) Find an expression for this current ?(e) for the magnetic field it produces. Determine the values of the quantities(f) E(vector) ? B(vector)(g) E² - c² B² in both reference frames, and show that these quantities are invariant. Your result gives a hint at how electric and magnetic fields transform, and demonstrates one instance of the fact that E(vector) ? B(vector) and (g) E² - c² B² are always invariant.

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y = 1/V1 – v21c