Question

Please solve these!! It's electrodynamics.

Answer 1

☆Electric field strength:

》It is measure of the effect produced by a electric charge by emitting elctric fields.

》it varies according to the distance,we move away from emitting source.

》$\bf{ E= \dfrac{KQ}{r²}}$

( 'k' is electrostatic force constant, Q= source charge responsible for emitting E, r= distance from the source to that point where the field has to be measured)

》From above we can see as distance increases, the field strength decreases.

☆Solution:

first see the above image!

(1). Case 1

• $\rm E_A = \dfrac{KQ}{r_A²}$

• $\rm 48 = \dfrac{KQ}{2²}$

• $\rm KQ = (48×4)$ ---------(1)

Case 2

• $\rm E_B = \dfrac{KQ}{r_B²}$

• $\rm E_B = \dfrac{48×4}{0.5²}$----(by 1 eq)

•$\rm E_B = \dfrac{48×4}{0.25}$

• $\bf{ E_B = 768 N/C}$

(2). As the distance increase ,E decrease.

see the above image ! you will totally get the answer

• we can compare the lengths here:

》OD>OA>OE>OB>OC

• Electric field order:

》 D < A < E < B< C = DAEBC

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