We come across various chemical reactions like rusting of iron, curdling of milk, respiration, digestion and growth. This solution contains questions, answers, images, explanations of the complete Chapter 10 titled The Fun They Had of Maths taught in class 9. Thus 4 resistors are needed to be connect. The cord remains cold due to its low resistance and dos not glow. The electric lamps glow at very high temperature. Which of the following terms does not represent electrical power in a circuit? Question 2 Define the unit of current.
As of now we have not provided the options to download the notes from our website. After you have studied lesson, you must be looking for answers of its questions. Go back to main page or move to of page. Why do we apply paint on iron articles? Q 12: Several electric bulbs designed to be used on a 220 V electric supply line, are rated 10 W. Thus, image is virtual, erect and diminished.
Please send your queries at contact ncerthelp. How is it connected in a circuit? Question 5: What is a the highest b the lowest total resistance that can be secured by combination of four coils of resistances 4 Ω, 8 Ω, 12 Ω, 24 Ω? You can also Download to help you to revise complete Syllabus and score more marks in your examinations. It covers answers to all the in between exercises and exercises are given at the end of the chapter. Answer: The potential difference between two points is said to be 1 volt if 1 joule of work is done in moving 1 coulomb of electric charge from one point to the other. Question 7: B 1, B 2 and B 3 are three identical bulbs connected as shown in figure. What would be the readings in the ammeter and the voltmeter? Go back to main page or move to of page.
Important derivations, numerical problems, practice test and assignments will also uploaded time to time. Solution: i The circuit diagram is shown in figure. Question 5: Use the data in Table 12. If a number is non-terminating and repeating then it is rational and if non-terminating and non-repeating then it is irrational. Perimeter of a Quadrilateral is the sum of its four sides.
This is what we desire in part i b Two resistor in series Two 6 Ω resistors are in series. These solutions not only help the students to clear their doubts but can also help them to have an in-depth knowledge of the concepts. You have to know that science is a scoring subject and if you score well, you have better opportunities. Topics associated to Resistance of a System of Resistors that Further Includes Resistors in Series and Resistors in Parallel shall be dealt within this chapter. Question 4 Why are coils of electric toasters and electric irons are made of an-alloy rather than a pure metal? When it is operated on 110 V, the power consumed will be a 100 W b 75 W c 50 W d 25 W Answer: Question 4: Two conducting wires of same material and of equal lengths and diameters are first connected in series and then parallel in a circuit across the same potential difference. Q 15: Two lamps, one rated 100 W at 220 V, and the other 60 W at 220 V, are connected in parallel to electric mains supply.
Hence this rational will not have terminating decimal expansion. Find the value of the resistance of the resistor. Explain the following in terms of gain or loss of oxygen with two examples each. Determine the power of the motor and the energy consumed in 2 h. The current flowing through a resistor connected in an electric circuit and the potential difference applied across its ends are shown in figure alongside.
Page 202 Question 1: Name a device that helps to maintain a potential difference across a conductor. A hot plate of an electric oven connected to a 220 V line has two resistance coils A and B, each of 24? When it is operated on 110 V, the power consumed will be : a 100 W b 75 W c 50 W d 25 W Answer: d 25 W Question 4 Two conducting wires of the same material and of equal lengths and equal diameters are first connected in series and then parallel in a circuit across the same potential difference. Answer: Question 11: Show how you would connect three resistors, each of resistance 6 Ω , so that the combination has a resistance of i 9 Ω , it 4 Ω. It comprises a cell, ammeter, voltmeter, plug key, etc. Write the balanced chemical equations for the following reactions.
The topics and sub-topics in Chapter 12 Electricity are given below. While the rest of bulbs in parallel circuit will continue to glow without getting disturbed because in parallel combination, current gets additional paths to flow. Thus iron is a better conductor because it has lower resistivity than mercury. . Score good marks in your science exams if you know what and how much to write.
How much does the resistance change if the diameter is doubled? The topics and sub-topics in Chapter 1 Chemical Reactions and Equations are given below. So this chapter is important from examination point of view. We also share useful articles on our facebook page to help you in your board examination. It is given in the question that both the bulbs are connected in parallel combination. The magnesium ribbon is cleaned by sand paper to remove this layer so that the underlying metal can be exposed into air.
Hence, the sum of the resistances will give the value of R. The voltage is plotted on x-axis and current is plotted on y-axis. All Chapter 1 - Chemical Reactions and Equations Exercise Questions with Solutions to help you to revise complete Syllabus and Score More marks. Magnesium chloride aq + Hydrogen g Question 9. These rays meet at the other side of the lens to form the image of the given object, as shown in the following figure. Go back to main page or move to of page.