Telangana SCERT Class 7 Science Chapter 7 Solution – Electricity Current And Its Effect. Here in this post we provides Class 7 Science Electricity Current And Its Effect Telangana State Board Solution. Telangana State Board English Class VII Medium Students can download this Solution to Solve out Improve Your Learning Questions and Answers.
Telanagana State Board Class 7 Science Chapter 7 Electricity Current And Its Effect Solution:
Improve your learning: –
(1) Draw the symbols of the following electric components.
(a) Cell
(b) Battery
(c) Switch
(d) Electric bulb
Ans: –
(2) Draw an electric circuit diagram consisting of a cell, a bulb and an electric switch.
Ans: –
(3) In a series connection of bulbs, if one bulb fails, why do all other bulbs go off?
Ans: – In a series connection of bulbs, if one bulb gets fused or fails, all the other bulbs in the series will stop glowing. It means that if one bulb is disconnected the other bulbs do not glow, in series connection bulbs will connect to a dry cell. In this connection electricity flows through a single line without any line distribution. That’s why if a single circuit break, the total power or connection car break down.
(4) Write the difference between series connection and parallel connection.
Ans: –
The difference series connection and parallel connection: –
The difference is that in series connection circuit have flow the same amount of current through all the components which placed in it. Like three torch bulbs connect in series connection, the brightness of each three bulbs are high and they all are connected through a single line.
But in parallel connection all the components are placed in parallel with each other. That is one and of each the other ends of the three bulbs are connected to another wire. In parallel connection all three bulbs glow dimly.
In series connection if one bulb is disconnected all the other bulbs also get disconnected.
In parallel connection if one bulb is disconnected the other bulbs continue to glow.
Series connection used in decorative events, like marriage or other festivals.
Parallel connection can be observed in our household electric circuit.
(5) What is the advantage of Miniature circuit breaker?
Ans: – These days miniature circuit Breaker (MCB) is increasing being used in place of fuses.
The advantage miniature circuit breakers have over fuses is that they can be rest (manually or automatically) to restore normal operation, whereas fuses need to be replaced after every single operation. The MCB can be reset by hand and the circuit becomes complete once again.
(6) Fill in the blanks
(a) Longer line in the symbol for a cell represents its ______ terminal
Ans: – Positive(+ve)
(b) Smaller line in the symbol for a cell represents its ______ terminal.
Ans: – negative(-ve)
(c) The combination of two or more cells is called a ______
Ans: – Battery
(d) Safety device used in electrics circuit is ______
Ans: – Fuse
(e) The device used to close or open an electric circuit is ________
Ans: – Electric Switch
(7) Mark ’T’ of the statement is true and ‘F’ if it is false. Give reasons for choice of answers.
(a) In series circuit the electricity has only one path. ( T / F)
Ans. T.
Reason: The current has only path to follow as all the applianas are connected in same line.
(b) In parallel circuit the electricity has more than one path. ( T / F)
Ans. T
Reason: – In parallel connection the appliances are connected separately. So there are different path for the flow of current.
(c) To make a battery of two cells, the negative terminal of one cell is connected to the negative terminal of the other cell. (T / F )
Ans. F
Reasons: To make a battery of two cells, the positive terminal of one cell is connected to the negative terminal of the other cell
(d) When the electric current through the fuse exceeds a certain limit, the fuse wire melts and breaks. ( T / F )
Ans. T
Reason: The current in the circuit is too high the fuse wire gets hot and melts.
(e) The switch is used to close or open an electric circuit. ( T / F )
Ans. T
Reasons: The switch is used to close or open on electric current.
(8) Choose Current answer:
(i) Arun buys four bulbs of 15w, 40w, 60w and 100 w respectively, which one should be used in his room as a night bulb.
(a) 15w
(b) 40w
(c) 60w
(d) 100w
Ans. A.
(ii) Device used to close or open an electric circuit is
(a) Electric bulb
(b) Battery
(c) Switch
(d) Fuse
Ans. C
(iii) Which one of the following is used as a for light source.
(a) Cassette player
(b) Electric mixer
(c) Rice cocker
(d) Table lamp
Ans. D.
(iv) Safety device used in electric circuit is –
(a) Electric bulb
(b) Battery
(c) Switch
(d) Fuse
Ans. D.
(9) Visit your classmate’s house. Find out the meter readings of three months. Record your observations. Ask your parents about how electricity bill is paid?
Ans: – The electricians come home and they check voltage and the bill is passed to people home, then the people can pay bill online or offline to both procedures. In this way by the amount of volt used by the people, they ca paid their bills.
(12) Match the following
| (1) Cell (2) | (a) used to open or close a circuit |
| (2) Switch (5) | (b) Safety device used in electric circuit |
| (3) Circuit (3) | (c) A complete path for the flow of an electric current |
| (4) Miniature circuit breaker (4) | (d) Reset by hand circuit be comes complete once again. |
| (5) Fuse (1) | (e) A device which converts chemical energy into electrical energy. |
