Department of Pre-University Education, KarnatakaPUC Karnataka Science Class 12

# And → E and → B Denote Electric and Magnetic Fields in a Frame S and → E → and → B in Another Frame S' Moving with Respect to S at a Velocity → V Two of the Following - Physics

Short Note

and vecE and  vecBdenote electric and magnetic fields in a frame S and vecE→ and vecB in another frame S' moving with respect to S at a velocity vecV Two of the following equations are wrong. Identify them.
(a) B_y^, =  B_y + (vE_z)/c^2

(b) E_y^' = E_y - (vB_z)/(c^2)

(c) Ey = By + vE_z

(d) E_y = E_y + vB_z

#### Solution

(b) E_y^' = E_y - (vB_z)/(c^2)

(c) Ey = By + vE_z
Electric force due to a charged particle is q E and magnetic force is q V B.

We can sort out the two wrong equations using dimensional analysis. Now, equating the above two forces. we get:

E = V B

Hence, analysing the answers using dimensional analysis, we see that the second term on the RHS of the equations (b) and (c) are not dimensionally correct. Thus, the options (b) and (c) are wrong.

Is there an error in this question or solution?

#### APPEARS IN

HC Verma Class 11, Class 12 Concepts of Physics Vol. 2
Chapter 12 Magnetic Field
MCQ | Q 10 | Page 230