Physics
Fill in the blanks:
(a) Like charges …………… while unlike charges …………… .
(b) Mercury is a …………… of electricity while pure water is …………… of electricity.
(c) An ebonite rod when rubbed with fur acquires the …………… charge.
(d) When an uncharged conductor is brought in contact with the disc of a gold leaf electroscope, its leaves …………… .
(e) Charge is shared in charging a conductor by the method of …………… .
Answer
(a) Like charges repel while unlike charges attract.
(b) Mercury is a conductor of electricity while pure water is insulator of electricity.
(c) An ebonite rod when rubbed with fur acquires the negative charge.
(d) When an uncharged conductor is brought in contact with the disc of a gold leaf electroscope, its leaves will remain unchanged.
(e) Charge is shared in charging a conductor by the method of conduction.
Related Questions
Assertion (A) : Lightning is a natural example of static electricity.
Reason (R) : Lightning occurs due to the accumulation of same charges in clouds and earth's surface.
- Both A and R are true and R is the correct explanation of A
- Both A and R are true and R is not the correct explanation of A
- Assertion is true but reason is false
- Assertion is false but reason is true
Assertion (A) : Conductors can be charged by friction.
Reason (R) : Conductors allow charges to flow through them and do not retain static charges.
- Both A and R are true and R is the correct explanation of A
- Both A and R are true and R is not the correct explanation of A
- Assertion is true but reason is false
- Assertion is false but reason is true
Write true or false for each statement:
(a) The number of electrons and protons in an atom are same.
(b) If the charge is not in motion, we call it static electricity.
(c) Human body is a conductor of electricity.
(d) When an ebonite rod is rubbed with fur, the electrons move from ebonite to fur.
(e) When a glass rod is rubbed with dry silk cloth, the electrons move from glass to silk.
(f) The cap of gold leaf electroscope is made of copper.
(g) If a glass rod rubbed with silk is brought near the cap of a negatively charged electroscope, the divergence of leaves will decrease.
(h) In induction, a positively charged body can make an uncharged body positively charged.
(i) A lightning conductor saves the building from lightning.
(j) When a comb is rubbed with dry hair both comb and paper get similarly charged.
(k) A glass rod rubbed with silk repels an ebonite rod rubbed with fur.
(l) When an ebonite rod is rubbed with fur, the protons move from the ebonite rod to the fur.
(m) A conductor has a large number of free electrons.
(n) An ebonite rod can be charged by touching it with a charged copper rod.
(o) To find whether a body is charged or not, an uncharged electroscope is used.
(p) To find whether the charge on a body is positive or negative, an uncharged electroscope is used.
(q) If a negatively charged rod is brought near a negatively charged pith ball electroscope, the pith ball will be stuck with the rod.
Match the following:
Column A Column B (a) Two like charges (i) negative charge (b) Two unlike charges (ii) repel (c) Silver is a (iii) insulator (d) Silk is an (iv) attract (e) Ebonite rod rubbed with fur acquires (v) conductor