Question 1 : Which of the following is most suitable for the core of electromagnets

Question 2 : A magnet is placed on a paper in a horizontal plane for locating neutral points. <img style='object-fit:contain' width='9' height='20' src="https://storage.googleapis.com/teachmint/question_assets/NEET/5ea286113c680714de9a7dd7"> dip needle placed at the neutral point will be horizontal at the

Question 3 : A small rod of bismuth is suspended freely between the poles of a strong electromagnet. It is found to arrange itself at right angles to the magnetic field. This observation establishes that bismuth is

Question 4 : A bar magnet of magnetic moment {tex} M {/tex} is placed at right angles to a magnetic induction {tex} B {/tex} . If a force {tex} F {/tex} is experienced by each pole of the magnet, the length of the magnet will be

Question 5 : The effect due to uniform magnetic field on a freely suspended magnetic needle is as follows

Question 6 : The magnetising field required to be applied in opposite direction to reduce residual magnetism to zero is called

Question 8 : Which of the following is responsible for the earth's magnetic field?

Question 10 : The bob of a simple pendulum is replaced by a magnet. The oscillation are set along the length of the magnet. A copper coil is added so that one pole of the magnet passes in and out of the coil. The coil is short-circuited. Then which one of the following happens

Question 11 : A current carrying loop is placed in a uniform magnetic field. The torque acting on it does not depend upon

Question 12 : When a long wire carrying a steady current is bent into a circular coil of one turn, the magnetic induction at its centre is B. When the same wire carrying the same current is bent to form a circular coil of n turns of a smaller radius, the magnetic induction at the centre will be

Question 13 : A very long straight wire carries a current I. At the instant when a charge {tex} + Q {/tex} at point {tex} P {/tex} has velocity {tex} \vec { v } {/tex} as shown, the force on the charge is<br> <img style='object-fit:contain' src='https://storage.googleapis.com/teachmint/question_assets/NEET/5ea3e5dc2ab9323e2d4de6d2' class="uploaded-image" />

Question 14 : A vibration magnetometer is placed at south pole, then the time period will be

Question 15 : An electron and a proton are projected at right angles to a uniform magnetic field with the same kinetic energy. Then

Question 17 : If an ammeter is to be used in place of a voltmeter, then we must connect with the ammeter a

Question 18 : The radius of the path of an electron moving at a speed of <img style='object-fit:contain' width=77 height=20 src="https://storage.googleapis.com/teachmint/question_assets/NEET/5ea1c0ac27ce131ff7c0922a"> perpendicular to a magnetic field 5 <img style='object-fit:contain' width=56 height=20 src="https://storage.googleapis.com/teachmint/question_assets/NEET/5ea1c0ac27ce131ff7c0922b"> is nearly

Question 19 : If a magnetic substance is kept in a magnetic field then which of the following substance is thrown out?

Question 20 : Hysteresis loops for two magnetic materials A and B are given below : <br> <img style='object-fit:contain' src="https://data-screenshots.sgp1.digitaloceanspaces.com/5d60fc31ca41306d7a3240ee.jpg" /> <br> These materials are used to make magnets for elecric generators, transformer core and electromagnet core. Then it is proper to use:<br>

Question 21 : The force between two parallel current carrying wires is independent of

Question 26 : Two wires with currents 2{tex} \mathrm { A } {/tex} and {tex}1{/tex} A are enclosed in a circular loop. Another wire with current 3{tex} \mathrm { A } {/tex} is situated outside the loop as shown. The {tex} \oint \overrightarrow { \mathrm { B } } \cdot \mathrm { d } \vec { l } {/tex} around the loop is<br><img style='object-fit:contain' src="https://storage.googleapis.com/teachmint/question_assets/NEET/5d60ef0de5db655bbf10a47d"><br>

Question 27 : A 10 eV electron is circulating in a plane at right angles to a uniform field at magnetic induction {tex} 10 ^ { - 4 } \mathrm { Wb } / \mathrm { m } ^ { 2 } ( = 1.0 {/tex} gauss). The orbital radius of the electron is

Question 28 : A uniform electric field and a uniform magnetic field exist in a region in the same direction. An electron is projected with a velocity pointed in the same direction. Then the electron will

Question 29 : A short magnet oscillates in an oscillation magnetometer with a time period of 0.10{tex} \mathrm { s } {/tex} where the earth's horizontal magnetic field is 24{tex} \mu T {/tex} . A downward current of 18{tex} \mathrm { A } {/tex} is established in a vertical wire placed 20{tex} \mathrm { cm } {/tex} east of the magnet. Find the new time period.

Question 30 : A loosely wound helix made of stiff wire is mounted vertically with the lower end just touching a dish of mercury. When a current from a battery is started in the coil through the mercury

Question 31 : Torques {tex} \tau _ { 1 } {/tex} and {tex} \tau _ { 2 } {/tex} are required for a magnetic needle to remain perpendicular to the magnetic fields at two different places. The magnetic fields at those places are {tex} \mathrm { B } _ { 1 } {/tex} and {tex} \mathrm { B } _ { 2 } {/tex} respectively; then ratio {tex} \frac { \mathrm { B } _ { 1 } } { \mathrm { B } _ { 2 } } {/tex} is

Question 33 : The deflection in a galvanometer falls from 50 division to 20 when a 12 ohm shunt is applied. The galvanometer resistance is

Question 34 : A bar magnet has a length 8{tex} \mathrm { cm } {/tex} . The magnetic field at a point at a distance 3{tex} \mathrm { cm } {/tex} from the centre in the broad side-on position is found to be {tex} 4 \times 10 ^ { - 6 } \mathrm { T } {/tex} . The pole strength of the magnet is.

Question 35 : If the susceptibility of dia, para and ferro magnetic materials are {tex} \chi _ { \mathrm { d } } , \chi _ { \mathrm { p } } , \chi _ { \mathrm { f } } {/tex} respectively, then