An electron in potentiometer wire experiences a force 2.4 × 10-19 N. The length of potentiometer wire is 6 m. The e.m.f. of the battery connected across the wire is (electronic charge = 1.6 × 10 -19C)

Question

An electron in potentiometer wire experiences a force 2.4 × 10-19 N. The length of potentiometer wire is 6 m. The e.m.f. of the battery connected across the wire is (electronic charge = 1.6 × 10 -19C) (A) 6 V (B) 9 V (C) 12 V (D) 15 V

Tardigrade Admin · Accepted Answer

Force experienced by electron F=q E where E= Electric field intensity ∴ 2.4 × 10-19=1.6 × 10-19 E ⇒ E=1.5 N / m Moreover E= potential gradient E =(d V/d l) ∴ E × l =V ⇒ V=1.5 × 6=9 V

Q. An electron in potentiometer wire experiences a force $2.4 \times 1 0^{- 19} N$ . The length of potentiometer wire is $6 m$ . The e.m.f. of the battery connected across the wire is (electronic charge $= 1.6 \times 10^{- 19} C$ )

$6 V$

$9 V$

$12 V$

$15 V$

Force experienced by electron $F = qE$
where $E =$ Electric field intensity
$∴ 2.4 \times 1 0^{- 19} = 1.6 \times 1 0^{- 19} E \Rightarrow E = 1.5 N / m$
Moreover $E =$ potential gradient
$E = \frac{d V}{d l}$
$∴ E \times l = V \Rightarrow V = 1.5 \times 6 = 9 V$

Q. An electron in potentiometer wire experiences a force 2.4×10−19N. The length of potentiometer wire is 6m. The e.m.f. of the battery connected across the wire is (electronic charge =1.6×10−19C)

6V

9V

12V

15V