Advertisements
Advertisements
Questions
Draw magnetic field lines produced around a straight current carrying conductor passing through a cardboard. How will the strength of the magnetic field change when the point where magnetic field is to be determined is moved away from the conductor?
How will the strength of the magnetic field change when the point where the magnetic field is to be determined is moved away from the straight wire carrying constant current? Justify your answer.
Advertisements
Solution
Using a compass needle we can determine the magnetic field. When we move away from the compass needle from the straight wire, the deflection of the needle decreases which implies the strength of the magnetic field decreases, as the strength of magnetic field produced by a straight wire at any point is inversely proportional to the distance of the point from the wire.
RELATED QUESTIONS
Do you think an electromagnet can be used for separating plastic bags from a garbage heap? Explain.
What device reverses the current?
If fuse of 250 mA, 500 mA, 1 A, 5 A and 10 A were available, which one would be the most suitable for protecting an amplifier rated at 240 V, 180 W?
In the Activity shown below, how do we think the displacement of rod AB will be affected if
- current in rod AB is increased
- a stronger horse-shoe magnet is used
- length of the rod AB is increased?
|
Observe the following diagram and choose the correct alternative:
Paheli does not have a night lamp in her room. She covered the bulb of her room with a towel at the night to get dim light. Has she taken the right step? Give one reason to justify your answer.
Why do we cover plug pin holes which are within the reach of children with cellotape or a plastic cover when not in use?
What do you mean by the magnetic effect?
A wire with green insulation is usually the live wire of an electric supply.
The figure given below shows the magnetic field around the conductor. Study it and answer the questions:
- What changes are caused by increasing current?
- What do you see when the magnetic needle is kept a little away from the wire?
- In the second part of the figure, the iron filings arrange themselves in a circular manner around the wire. Why does this happen?
