Question

Guys help me out plzz​

Answer 1

• define the unit of current
• The SI unit for measuring an electric current is the ampere, which is the flow of electric charge across a surface at the rate of one coulomb per second.

• draw circuit symbol for rheostat
• answer attached

• why don't two magnetic lines never intersect
• Two magnetic field lines do not intersect each other because if there was point of intersection, The compass needle would point towards 2 directions. Which means that the magnetic field has two different directions, which is not possible.

• draw a diagram representing uniform magnetic field
• answer attached

• what is role of split rings in an electric
• motor Role of Split Ring in an Electric Motor

Split ring is used for reversing the direction. of current in the coil. ... Therefore, after every

• half rotation of the coil the direction of the couple rotating the coil remains the same and the coil continues its rotation in the same direction.

• define critical angel
• the angle of incidence beyond which rays of light passing through a denser medium to the surface of a less dense medium are no longer refracted but totally reflected.

• write the properties of a good fuel
• It should possess high calorific value.

It should have proper ignition temperature. ...

It should not produce poisonous products during combustion. ...

It should have moderate rate of combustion.

Combustion should be easily controllable i.e., combustion of fuel should be easy to start or stop as and when required.

the questions not written :::;:

3) and 7)

Answer 2

Answer:

1) The SI unit of electric current is the ampere, or amp, which is the flow of electric charge across a surface at the rate of one coulomb per second. The ampere (symbol: A) is an SI base unit 15 Electric current is measured using a device called an ammeter.

2) In the image.....

3) The calculation for wattage of a single phase circuit is found as [Watts = Amps x Volts].

4) In the image...

5) Magnetic field is a vector. The diagram or sketch of a magnetic field will show how a magnetic force is acting in that area. A uniform magnetic field is presented by parallel & equidistant straight lines all pointing in the same direction.

In the image is the diagram

6) Role of Split Ring in an Electric Motor

Split ring is used for reversing the direction of current in the coil. For the continuous rotation of the coil in the same direction, the current in the coil must be reversed. Therefore, after every half rotation of the coil the direction of the couple rotating the coil remains the same and the coil continues its rotation in the same direction.

7) Convex mirrors always form virtual images because the focal point and the centre of curvature of the convex mirror are imaginary points and that cannot be reached. So the image is formed inside the mirror and cannot be projected on a screen. The image formed look smaller than the object from a distance but it gets larger as the object is brought closer to the mirror.

8) The angle of incidence beyond which rays of light passing through a denser medium to the surface of a less dense medium are no longer refracted but totally reflected.

9)

1. It should possess high calorific value.

2. It should have proper ignition temperature. The ignition temperature of the fuel should neither be too low nor too high.

3. It should not produce poisonous products during combustion. In other words, it should not cause pollution o combustion.

4. It should have moderate rate of combustion.

5. Combustion should be easily controllable i.e., combustion of fuel should be easy to start or stop as and when required.

6. It should not leave behind much ash on combustion.

7. It should be easily available in plenty.

8. It should have low moisture content.

9. It should be cheap.

10. It should be easy to handle and transport.