Electrostatics - Day 1

If a body charged by rubbing it, its weight

• Always decreases slightly

• Always increases slightly

• May increase slightly or may decrease slightly

• Remain precisely the same

In winter season, a mild spark is often seen when a man touches somebody else's skin. Why?

• Due to lack of humidity and rubbing with clothes, charge accumulate on human body which is discharged via sparking

• Due to cold, electrostatic charge on body finds a lower resistance path to the skin of other's body

• The static charge on sweaters worn by the two persons is different, hence discharge through sparking occurs

• Similar to the lighting, extremely high potential exists on both the bodies and hence they discharge through sparking

There are two charges +2 μC and −3 μC. The ratio of forces acting on them will be 

• 2:3

• 1:1

• 3:2

• 4:9

When a comb is rubbed with hair, it attracts paper bits. Choose the right explanation.

• Bits of paper gets attracted due to gravitational force

• Due to electromagnetic effect, bits of paper are attracted

• Comb gets charged by friction and attract bits of paper

• None of these

A spherical conducting ball is suspended by a grounded conducting thread. A positive point charge is moved near the ball. That ball will

• Be attracted to the point charge and swing toward it

• Be repelled from the point charge and swing away from it

• Not be affected by the point charge

• None of these

The field lines are ______ to the surface of the charge.

• Parallel

• Perpendicular

• At an angle of 45⁰

• At an angle of 60⁰

Electric field lines starting from a positive charge end at

• Infinity only

• Another positive charge

• Negative charge

• Either at a negative charge or at infinity

Electrostatic field lines do not form any closed loops. State true or false:

• TRUE

• FALSE

Two field lines cannot cross each other. State true or false

• TRUE

• FALSE

Electrostatic field finds its application in

• Transformers

• Electron microscope

• Air conditioners

• crane