The intensity of electric field required to balance a proton of mass 1.7 × 10-27 kg and charge 1.6 × 10-19 C is nearly

Question

The intensity of electric field required to balance a proton of mass 1.7 × 10-27 kg and charge 1.6 × 10-19 C is nearly (A) 1 × 10-7 V / m (B) 1 × 10-5 V / m (C) 1 × 107 V / m (D) 1 × 105 V / m

Tardigrade Admin · Accepted Answer

Since q E=m g ⇒ E=(m g/q)=(1.7 × 10-27 × 9.8/1.6 × 10-19) =10.0 × 10-8=1 × 10-7 V / m

Q. The intensity of electric field required to balance a proton of mass $1.7 \times 1 0^{- 27} k g$ and charge $1.6 \times 1 0^{- 19} C$ is nearly

$1 \times 1 0^{- 7} V / m$

$1 \times 1 0^{- 5} V / m$

$1 \times 1 0^{7} V / m$

$1 \times 1 0^{5} V / m$

Since $qE = m g$
$\Rightarrow E = \frac{m g}{q} = \frac{1.7 \times 1 0 ^{- 27} \times 9.8}{1.6 \times 1 0 ^{- 19}}$
$= 10.0 \times 1 0^{- 8} = 1 \times 1 0^{- 7} V / m$

Q. The intensity of electric field required to balance a proton of mass 1.7×10−27kg and charge 1.6×10−19C is nearly

1×10−7V/m

1×10−5V/m

1×107V/m

1×105V/m