The region of space around a charged object is called an electric field

PHYSICS · Multi-part · CBSE · Physics · Electric Charges and Fields · Electric Charges and Fields

Problem

The region of space around a charged object is called an electric field. This electric field exerts a force on any charged particle in it. (a) How does this force depend on - i the amount of charge on the charged particle in the field? - ii the amount of charge that the object creating the field has? - iii the distance between the charged object creating the field and the charged particle in the field? (b) State Coulomb's law in - i words. - ii an equation, with explained terms. (c) The constant in Coulomb's law,

k

(usually called the Coulomb constant), has the value

9 \times 10^9 \text{ Nm}^2\text{C}^{-2}

if the space occupied by an electric field is a vacuum or air. Calculate the force between - i a charge of

+50 \text{ nC}

and another charge of

-20 \text{ nC}

that are

30 \text{ cm}

apart in air. - ii a charge of

+30 \mu\text{C}

and another charge of

+20 \mu\text{C}

that are

5 \text{ mm}

apart in air. - iii an electron and a proton that are

100 \text{ pm}

apart in a vacuum. - iv an alpha particle of charge

6.4 \times 10^{-19} \text{ C}

and a gold nucleus of charge

1.26 \times 10^{-17} \text{ C}

that are

3 \text{ fm}

apart in a vacuum.

Related theory

Browse the problem library