NCTB Class 9-10 Science Chapter 12 “Electricity in Daily Life” Solution
Bangladesh Board Class 9-10 Science Solution Chapter 12 Electricity in Daily Life Solution Exercises Question and Answer by Experienced Teacher.
NCTB Solution Class 9-10 Chapter 12 “Electricity in Daily Life”:
|
Board |
NCTB Bangladesh Board |
| Class |
9 – 10 (Nine – Ten Classes) |
|
Subject |
Science |
| Chapter |
Twelve |
|
Chapter Name |
Electricity in Daily Life |
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Multiple choice question.
1) Which one is the symbol of ammeter ?
Answer:- b)
2) In the process of electrolysis coating is given,
A) Nickel on iron
B) iron on zinc
C) Gold on copper
a) I and ii b) I and iii
c) ii and iii d) I, ii, and iii
Answer:- b) I and ii
Read the paragraph below and answer the questions 3 and 4.
Ripon lives in bakshigonj. Here usually load shedding occurrs. For this reason he is facing difficulties in many works. Ripon
3) Applicable for the instrument fitted as an alternative of electricity.
a) It is run by alternating current
b) It is also charged in low voltage
c) It is connected with the outputs of the current.
a) I and ii b) I and iii
c) ii and iii d) I,ii and iii
Answer:-I, ii and iii
4) The cause of the problem of bakshigonj?
1) The system loss of electricity.
2) The defects in the method of supply.
3) The production of electricity is less than the demand.
a) I and ii b) I and iii
c) ii and iii d) I, ii and iii
Answer:- d) I, ii, and iii
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Creative questions
Que.1] mrs. Monsurakhanom is a conscious house- wife. She is very cautious of using electricity in the house. She enkindles 5 bulbs of 100 watts for average 6 hours daily. She observed that the electric bill submitted to her is excessive recently. For this, she replaced the bulbs and fitted 5 energy saving bulbs of 20 watt each.
1) What is electric power?
Answer:- the amount of electrical energy spent or changed into Another energy (light, heat, mechanical energy etc.) Per second by an electric machine is called electric power.
2) There is written 220 volt 60 watt on the body of a bulb , what is the meaning of this?
Answer:-On the body of bulbs there is written 220V – 60 W on a bulb , it means when the bulb is connected with 220 V potential difference, the bulb will be enkindled With maximum luminosity . Then it will convert 60 joule electrical energy into light and heat energy.
3) What amount of total electric bill monsurakhanom was charged before the rate of 5 taka per unit ?
Answer:-
Consumed energy = ( p× t ) / 1000 unit
= 5 × 100 (30×6)/1000 unit
= 500(180)/1000 unit
= 90 unit.
Now the price is 5 taka per unit, then total expenses for that consumed amount of electricity will be –
Total electric expense = 90×5 taka
= 450 taka.
So , the amount of total electric bill mansurakhanom was charged before at the rate of 5 taka is 450 taka.
4) Subsequently by changing the bulbs what was the benefit of monsurakhanom. Give your opinion with arguments.
Answer:-in the ordinary bulbs, light is created by heating a metal filament and so a huge amount of energy was required . There are twotyoea of energy saving bulbs, CFL (COMPACT FLUORESCENT LAMP) and LED (LIGHT EMITTING DIODE) Bulbs . Thus energy saving bulbs can save 20% -80% electricity. And can last 3 to 25 times more than normal bulbs. Thus monsurakhanom saved 20 – 80 % energy by changing the bulbs.
Que.2] see the figure and answer the question.
A) What is electrolysis?
Answer:- the process of separating positive and negative parts of the molecules by passing electricity thorough a solution is called electrolysis.
B) What is meant by anode?
Answer:-An anode is an electrode through which the conventional current enters into a polarized electrical device. Anode is negative or reducing electrode.
C) How the electron will flow at the point B? Explain.
Answer:-in the chemical reaction in battery cell, electron dissipates from cathode to anode. as a result a potential difference between the anode and cathode appear. In this Position if anode and cathode are connected with a conducting wire, electrons flow from cathode to anode. Thus the electron flow at the point B.
D) Which one of the fig. P and Q is suitable for house wiring?
Give your opinion .
Answer:- the electricity that is suitable for house wiring is Q which is AC (Alternating current) because they change from positive to negative fifty times per second. In a normal battery cell, the potential difference is only 1.5 V compared with it, the electric supply in our houses is 220 V .Thus for house wiring Ac current is suitable that is Q.
