Exams › NEET › Physics

A body has a charge of $-80\,\mu\text{C}$. The number of additional electrons in it will be:

1. $5\times10^8$
2. $80\times10^{17}$
3. $5\times10^{14}$
4. $10^{17}$

Correct answer: $5\times10^{14}$

Solution

The number of excess electrons is $n = \dfrac{|Q|}{e}$. Here $|Q| = 80\times10^{-6}$ C, so $n = \dfrac{80\times10^{-6}}{1.6\times10^{-19}} = 5\times10^{14}$.

Related NEET Physics questions

• Which of the following statements is not true about Gauss's law?
• A positive charge and a negative charge are held in place and initially form a dipole. Then a uncharged conducting bar is placed in between them. How is the force between the charges affected?
• The capacitance of a parallel-plate capacitor is 10 μF without the dielectric. A material with dielectric constant 2 is used to fill half the thickness between the plates. The new capacitance is:
• A point charge is brought in an electric field. The electric field at a nearby point: This question has multiple correct options
• Assertion A capacitor can be given only a limited quantity of charge Reason A capacitor is an arrangement which can store sufficient quantity of charge
• A soap bubble of radius 3 cm is charged with surface charge density σ such that (σ²)/(ε₀)=0.4 S I units. The excess pressure inside the bubble in SI unit (surface tension of soap solution =3 × 10⁻³ N / m) is:

⚔️ Practice NEET Physics free + battle 1v1 →