Electricity
- What are the advantages of connecting electrical devices in parallel with the battery instead of connecting them in seri There is no division of voltage among the appliances when connected in parallel. The potential difference across each appliance is equal to... 1
- An electric lamp of 100 Ω, a toaster of resistance 50 Ω, and a water filter of resistance 500 Ω are connected https://youtu.be/MyGgXsAxodg 2
- Judge the equivalent resistance when the following are connected in parallel − (a) 1 Ω and 106Ω, (b) 1 Ω and 103Ω and (a) When 1 Ω and 10⁶ Ω are connected in parallel: Let R be the equivalent resistance. therefore 1/R = 1/1+1/10⁶ \\ R=10⁶/1+10⁶ simeq 10⁶/10⁶... 1
- Redraw the circuit of question 1, putting in an ammeter to measure the current through the resistors and a voltmeter to An ammeter should be connected in the circuit in series with the resistors. To measure the potential difference across the resistor it shoul... 1
- Draw a schematic diagram of a circuit consisting of a battery of three cells of 2 V each, a 5 Ω resistor Three cells of potential 2 V, each connected in series therefore the potential difference of the battery will be 2 V + 2 V + 2 V = 6V. The f... 1
- Use the data in Table 12.2 to answer the following - Table 12.2 Electrical resistivity of some substances at 20°C (a) Resistivity of iron = 10.0 x 10⁻⁸ Ω Resistivity of mercury = 94.0 x 10⁻⁸ Ω Resistivity of mercury is more than that of iron. This implie... 1
- Why are coils of electric toasters and electric irons made of an alloy rather than a pure metal? The resistivity of an alloy is higher than the pure metal. Moreover, at high temperatures, the alloys do not melt readily. Hence, the coils... 1
- Let the resistance of an electrical component remains constant while the potential difference across According to Ohm’s law V = IR ⇒ I=V/R ... (1) Now Potential difference is decreased to half ∴ New potential difference Vʹ=V/2 Resistance rem... 1
- Will current flow more easily through a thick wire or a thin wire of the same material, when connected to the The current will flow more easily through thick wire. It is because the resistance of a conductor is inversely proportional to its area of c... 1
- On what factors does the resistance of a conductor depend? The resistance of a conductor depends upon the following factors: Length of the conductor Cross-sectional area of the conductor Material of... 1
- How much energy is given to each coulomb of charge passing through a 6 V battery? The energy given to each coulomb of charge is equal to the amount of work which is done in moving it. Now we know that, Potential difference... 1
- What is meant by saying that the potential difference between two points is 1 V? If 1 J of work is required to move a charge of amount 1 C from one point to another, then it is said that the potential difference between t... 1
- Name a device that helps to maintain a potential difference across a conductor. Any source of electricity like battery, cell, power supply, etc. helps to maintain a potential difference across a conductor. 1
- Calculate the number of electrons constituting one coulomb of charge. One electron possesses a charge of 1.6 ×10⁻¹⁹C, i.e., 1.6 ×10⁻¹⁹C of charge is contained in 1 electron. ∴ 1 C of charge is contained in 1/1.... 1
- Define the unit of current The unit of electric current is ampere (A). 1 A is defined as the flow of 1 C of charge through a wire in 1 s. 1
- What does an electric circuit mean? A continuous and closed path of an electric current is called an electric circuit. An electric circuit consists of electric devices, source... 1