Class =10 physics

                             Light and reflection

All short type questions

very short answer type questions

q1. by what other name is the unit joule/coulomb calle

answer

the other name of the unit joule/coulomb is vol

volt is the si unit of electric potential or of electromotive force. it is represented by the letter v. volt is a representation of the potential difference between the two points of a current-carrying wire of 1 ampere such that when the power dissipates between these two points, it is equal to 1 wat

q2. which of the following statements correctly defines a vol

a) a volt is a joule per ampe

b) a volt is a joule per coulo

answe

the correct statement that defined a volt is b) a volt is a joule per coulo

volt is a joule per coulomb because joule is a unit of work done while coulomb is a unit for the charge. the ratio of work done to the charge is the definition of potential and volt is the unit of potential difference. therefore, it can be said that one joule per coulomb is equal to the unit of the potential difference which is also equal to one vol

(1 joule)/(1coulomb) = 1vo

q3. a) what do the letters p.d stand fo

b) which device is used to measure p.

answe

a) p.d stands for potential differen

potential difference is defined as the difference between the energy carried by the two points in the circuit. potential difference is also equal to the product of the amount of current and the resistance. following is the formula used for calculating potential differenc

v = i ×

wher

v is the volta

i is the curren

r is the resistanc

b) voltmeter is used for measuring p.

an instrument that is used for measuring the voltage in volts is known as a voltmeter. letter v is used for representing voltmeter between the two terminal

q4. what is meant by saying that the electric potential at a point is 1 vol

answer

the electric potential at a point is 1 volt means 1 joule of work is done in moving 1 unit of positive charge from infinity to that particular poin

q5. how much work is done when one-coulomb charge moves against a potential difference of 1 vol

answe

give

potential difference = 

charge to be moved = 

to fin

work done =

we know that the work done is given a

work done = potential difference × charge mov

= 1 × 1 = 

therefore, 1j of work is done to move 1c charge with 1v potential differenc

q6. what is the si unit of potential differenc

answe

the si unit of potential difference is volt. it is the difference of potential that one ampere of current is carried against one-ohm resistanc

q7. how much work is done in moving a charge of 2c across two points having a potential difference of 12

answe

give

potential difference = 1

charge moved = 

to fin

work done =

we know that the work done is given a

work done = p.d × charge mov

= 12 × 2 = 2

therefore, 24j of work is done to move a charge of 2c with a potential difference of 12

q8. what is the unit of electric charg

answe

coulomb is the unit of electric charge.  coulomb is defined as the charged that is transferred with the help of a steady current of one ampere in one secon

q9. define one coulomb charg

answe

one coulomb charge is defined as the quantity of charge that exerts a force of 9 × 109 newton on a charge which is placed at a distance of 1m from i

q10. fill in the following blanks with suitable word

a) potential difference is measured in …………… by using a ……….. placed in …………… across a componen

b) copper is a good ………..  plastic is an …………

answe

a) volts, voltmeter, parall

b) conductor, insulat

short answer type questio

q11. what is meant by conductors and insulators? give two examples of conductors and two of insulator

answer

conductors are defined as the materials through which electric current can flow. almost all the metals are examples of conductors. following are the examples of conductor

copper, silv

insulators are defined as the materials through which electric current cannot flow. non-metals are examples of insulators. following are the examples of insulator

plastic, cott

q12. which of the following are conductors and which are insulator

sulphur, silver, copper, cotton, aluminium, air, nichrome, graphite, paper, porcelain, mercury, mica, bakelite, polythene, mangan

answe

conductor: silver, copper, aluminium, nichrome, graphite, mercury, mangan

insulator: sulphur, cotton, air, paper, porcelain, mica, bakelite, polythe

q13. what do you understand by the term “electric potential” at a point? what is the unit of electric potentia

answe

the electric potential at a point is defined as the work done to move a unit positive charge from infinity to a particular point. volt is the unit of electric potentia

q14. a) state the relation between potential difference, work done, and charge move

b) calculate the work done in moving a charge of 4 coulomb from a point at 220 volts to another point at 230 vol

answe

a) potential difference = (work done)/(charge move

b) give

v1 = 22

v2 = 23

charge moved = 

potential difference =

we know that potential difference i

potential difference = v2 – 

= 230 – 220 = 

work done = potential difference × charge mov

= 10 × 4 = 4

therefore, the work done is 40j to move charge

q15. a) name a device that helps to measure the potential difference across a conducto

b) how much energy is transferred by a 12v power supply to each coulomb of charge which it moves around a circui

answe

a) voltmet

b) give

potential difference = 1

charge moved = 

work done =

we know that the work done is given a

work done = potential difference × charge mov

= 12 × 1 = 12 joul

therefore, 12j work is done on a 1c chargeeseds: ?1c2vn,err:t?r.s.0jed10v1s: ?4c0v0vn,d)r:t.d.l.r:l?neinr:ins?ons:ers:: s.nsorelr:….t.s:t.r:e.d.r:e?v.4jeds: ?d,2c2vn,r:v?e.r:e?e.1jeds: ?d,1c1vn,r:t?t.: t?s.detgee, re:cer:d?r?ltt.mbr:mbret?t.t.: d?12V

Charge moved = 1C

Work done = ?

We know that the work done is given as:

Work done = Potential difference × Charge moved

= 12 × 1 = 12 Joules

Therefore, 12J work is done on a 1C charge