Electric Charges and Fields

❗️❗️Electric Charges and Fields ❗️❗️

📌NCERT PICKS 📌

🔴  There is a spark or crackle when we take off oursynthetic clothes or sweater in dry whether. 

🔴 It is observed that if two glass rods rubbed with wool or 

silk cloth are brought close to each other, they repel each 

other. 

🔴  On rubbing two body, the mass of one body slightly get 

lowered. 

🔴  An ebonite rod held in hand can be charged by rubbing 

with funnel but a copper rod cannot be charged like this. 

🔴 When we touch a pith ball with an electrified plastic rod, 

some of the negative charges on rod are transferred. 

🔴  While calculating the force between the two charges 

from coulomb's law, never take into account, the sign of 

two charges. It just indicates nature of the force. 

🔴 The test charge used to measure electric field at point is 

taken as unit in magnitude or very small. 

🔴 Field lines are always directed from higher potential to lower potential. 

🔴 Neutral point is a point where resultant electric field is 

zero. 

🔴 When a charged particle enters with velocity at right 

angle to the uniform field the trajectory is parabola. 

🔴 A surface having same electric potential at every point is an equipotential surface. 

🔴 Work done in moving a charge along an equipotential 

surface is always zero. 

🔴  Relative permitivity of the material is also known as 

specific inductive capacitance.