Advertisements
Advertisements
प्रश्न
Advertisements
उत्तर
APPEARS IN
संबंधित प्रश्न
A line charge λ per unit length is lodged uniformly onto the rim of a wheel of mass M and radius R. The wheel has light non-conducting spokes and is free to rotate without friction about its axis (Figure). A uniform magnetic field extends over a circular region within the rim. It is given by,
B = − B0 k (r ≤ a; a < R)
= 0 (otherwise)
What is the angular velocity of the wheel after the field is suddenly switched off?
Name two devices in which electromagnets are used and two devices where permanent magnets are used.
What condition is necessary for the production of current by electromagnetic induction?
What do you understand by the term "electromagnetic induction"? Explain with the help of a diagram.
Name and state the law which determines the direction of induced current.
or
State Fleming’s right-hand rule.
The following diagram shows a fixed coil of several turns connected to a center zero galvanometer G and a magnet NS which can move in the direction shown in the diagram.
- Describe the observation in the galvanometer if
- The magnet is moved rapidly,
- The magnet is kept still after it has moved into the coil
- The magnet is then rapidly pulled out the coil.
- How would the observation in (i) of part (a) change if a more powerful magnet is used?
Which of the following scientist invented the rule of electromagnetic induction?
A cylindrical bar magnet (A) and similar unmagnetized cylindrical iron bar (B) are dropped through metallic pipe. The time taken to come down by ____________.
We can induce the current in a coil by ____________.
For making a strong electromagnet the material of the core should be ______.
