Doubtly
@Doubtly · Joined Feb 2021
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- Which of the following correctly describes the magnetic field near a long straight wire? (a) The field consists Correct option is d) The field consists of concentric circles centred on the wire 1
- What precaution should be taken to avoid the overloading of domestic electric circuits? The precautions that should be taken to avoid the overloading of domestic circuits are as follows: Too many appliances should not be connect... 1
- An electric oven of 2 kW is operated in a domestic electric circuit (220 V) that has a current rating of 5 A. Current drawn by the electric oven can be obtained by the expression, P = VI Where, Current = I Power of the oven, P = 2 kW = 2000 W Voltage... 1
- Name two safety measures commonly used in electric circuits and appliances. Two safety measures commonly used in electric circuits and appliances are Electric Fuse: An electric fuse is connected in series it protects... 1
- A rectangular coil of copper wires is rotated in a magnetic field. The direction of the induced current changes Correct option is c) half revolution 2
- Which sources produce alternating current? AC generators, power plants, etc., produce alternating current. 1
- Name some sources of direct current. Some sources of direct current are cell, DC generator, etc. 2
- State the principle of an electric generator. Electric generator works on the principle of electromagnetic induction. Electricity is generated by rotating a coil inside magnetic field. 1
- Explain different ways to induce current in a coil. The different ways to induce current in a coil are as follows: If a coil is moved rapidly between the two poles of a horse-shoe magnet, then... 2
- What is the role of the split ring in an electric motor? The split ring in the electric motor also known as a commutator reverses the direction of current flowing through the coil after every half... 1
- What is the principle of an electric motor? The principle of an electric motor is based on the magnetic effect of electric current. A current-carrying loop experiences a force and rota... 1
- State Fleming's left-hand rule. Fleming's left hand rule states that if we arrange the thumb, the centre finger, and the forefinger of the left hand at right angles to each... 1
- A positively-charged particle (alpha-particle) projected towards west is deflected towards north by a magnetic field. Correct option is d) upward 2
- In Activity 13.7 (page: 230), how do we think the displacement of rod AB will be affected if (i) current in rod AB The displacement of rod AB is increased due to magnetic force exerted on it, if : (i) If the current in the rod is increased then rod will b... 1
- Which of the following property of a proton can change while it moves freely in a magnetic field? Correct option is (c) velocity and (d) momentum 2
- The magnetic field inside a long straight solenoid-carrying current (a) is zero Correct option is d) is the same at all points 2
- The magnetic field in a given region is uniform. Draw a diagram to represent it. The magnetic field lines inside a current-carrying long straight solenoid are uniform. https://lh3.googleusercontent.com/-mxqndwiqY1I/YbYMJT... 2
- Consider a circular loop of wire lying in the plane of the table. Let the current pass through the loop clockwise Inside the loop = Pierce inside the table Outside the loop = Appear to emerge out from the table For downward direction of current flowing i... 1