Two charged pendulums of charges (2/3) μ C (10/3) mC are in equilibrium when they are 1 m apart. If the pendulums are identical then what will be the mass of each pendulum if the angle between the strings in equilibrium is 60°

Question

Two charged pendulums of charges (2/3) μ C (10/3) mC are in equilibrium when they are 1 m apart. If the pendulums are identical then what will be the mass of each pendulum if the angle between the strings in equilibrium is 60° (A) 1 Kg (B) 2 Kg (C) 2 √3 Kg (D) 3 √2 Kg

Tardigrade Admin · Accepted Answer

Force between the charges F=((9 × 109)((2/3) × 10-6)((10/3) × 10-3)/12)=20 N <img class="img-fluid question-image" alt="image" src="https://cdn.tardigrade.in/img/question/physics/2b7d5b65dff8d4f7637acd94dcbd5dae-.png" /> For equilibrium T sin 30°=20 T cos 30°= mg tan 30°=(20/ mg ) ⇒ m =2 √3 Kg

Q. Two charged pendulums of charges $\frac{2}{3} μ C &$ $\frac{10}{3} m C$ are in equilibrium when they are $1 m$ apart. If the pendulums are identical then what will be the mass of each pendulum if the angle between the strings in equilibrium is $6 0^{\circ}$

$1 K g$

$2 K g$

$23 K g$

$32 K g$

Force between the charges
$F = \frac{( 9 \times 1 0 ^{9} ) ( \frac{2}{3} \times 1 0 ^{- 6} ) ( \frac{10}{3} \times 1 0 ^{- 3} )}{1 ^{2}} = 20 N$

For equilibrium
$T sin 3 0^{\circ} = 20$
$T cos 3 0^{\circ} = m g$
$tan 3 0^{\circ} = \frac{20}{m g}$
$\Rightarrow m = 23 K g$

Q. Two charged pendulums of charges 32​μC& 310​mC are in equilibrium when they are 1m apart. If the pendulums are identical then what will be the mass of each pendulum if the angle between the strings in equilibrium is 60∘

1Kg

2Kg

23​Kg

32​Kg