Advertisements
Advertisements
प्रश्न
Which of the following four graphs may best represent the current-deflection relation in a tangent galvanometer?
Advertisements
उत्तर
curve
Since i ∝ tan θ , the only graph that represents this correlation is curve c.
APPEARS IN
संबंधित प्रश्न
State any two advantages of electromagnets over permanent magnets.
A dip circle is taken to geomagnetic equator. The needle is allowed to move in a vertical plane perpendicular to the magnetic meridian. The needle will stay ______.
A very long bar magnet is placed with its north pole coinciding with the centre of a circular loop carrying as electric current i. The magnetic field due to the magnet at a point on the periphery of the wire is B. The radius of the loop is a. The force on the wire is
Consider the situation of the previous problem. The directions of the magnetic field due to the dipole are opposite at
(a) P1 and P2
(b) Q1 and Q2
(c) P1 and Q1
(d) P2 and Q2
To measure the magnetic moment of a bar magnet, one may use
(a) a tangent galvanometer
(b) a deflection galvanometer if the earth's horizontal field is known
(c) an oscillation magnetometer if the earth's horizontal field is known
(d) both deflection and oscillation magnetometer if the earth's horizontal field is not known
Why is it not possible to make permanent magnets from paramagnetic materials?
The magnetic moment of the assumed dipole at the earth's centre is 8.0 × 1022 A m2. Calculate the magnetic field B at the geomagnetic poles of the earth. Radius of the earth is 6400 km.
If the earth's magnetic field has a magnitude 3.4 × 10−5 T at the magnetic equator of the earth, what would be its value at the earth's geomagnetic poles?
The magnetic field due to the earth has a horizontal component of 26 μT at a place where the dip is 60°. Find the vertical component and the magnitude of the field.
The needle of a dip circle shows an apparent dip of 45° in a particular position and 53° when the circle is rotated through 90°. Find the true dip.
A moving-coil galvanometer has a 50-turn coil of size 2 cm × 2 cm. It is suspended between the magnetic poles producing a magnetic field of 0.5 T. Find the torque on the coil due to the magnetic field when a current of 20 mA passes through it.
A short magnet produces a deflection of 37° in a deflection magnetometer in Tan-A position when placed at a separation of 10 cm from the needle. Find the ratio of the magnetic moment of the magnet to the earth's horizontal magnetic field.
A short magnet oscillates in an oscillation magnetometer with a time period of 0.10 s where the earth's horizontal magnetic field is 24 μT. A downward current of 18 A is established in a vertical wire placed 20 cm east of the magnet. Find the new time period.
Soft iron is used to make the core of the transformer because of its ______.
Which property of soft iron makes it useful for preparing electromagnet?
Answer in brief.
Explain one application of electromagnet.
The relation b/w magnetic susceptibility xm and relativ~ permeability µr is
A steel wire of length 1 has a magnetic moment m it is then bent into a semicircular arc. The new magnetic moment is
