Magnetic-Effect-Of-Current-And-Magnetism-Quiz-9

Magnetic Effect Of Current And Magnetism Quiz-9

Dear Readers,

As per analysis for previous years, it has been observed that students preparing for NEET find Physics out of all the sections to be complex to handle and the majority of them are not able to comprehend the reason behind it. This problem arises especially because these aspirants appearing for the examination are more inclined to have a keen interest in Biology due to their medical background. 

Furthermore, sections such as Physics are dominantly based on theories, laws, numerical in comparison to a section of Biology which is more of fact-based, life sciences, and includes substantial explanations. By using the table given below, you easily and directly access to the topics and respective links of MCQs. Moreover, to make learning smooth and efficient, all the questions come with their supportive solutions to make utilization of time even more productive. Students will be covered for all their studies as the topics are available from basics to even the most advanced. 

Q81. At the magnetic poles of the earth, a compass needle will be

•  Vertical
•  Bent slightly
•  Horizontal
•  Inclined at 45° to the horizontal

Solution
Earth’s field is the effect of complex convention currents in the magma, which must be described as several dipoles, each with a different intensity and orientation, the compass actually point to the sum of the effects of these dipoles. In other words, it aligns itself with the magnetic lines of force. Other factors, of local and solar origin, further complicate the resulting field. It may be all right to say that a compass needle points ”magnetic north” but it only roughly points to the north magnetic dipole. Hence, at the magnetic poles of the earth, a compass needle will be bent slightly.

Q82.The length of magnet is large compared to its width and breadth. The time period of its oscillation in a vibration magnetometer is 2 s. The magnet is cut along its length into three equal parts and these parts are then placed on each other with their like poles together. The time period of this combination will be

•  2/√3s
•  2/3s
•  2√3s
•  2s

Solution
                        

Q83.  Water is

•  Diamagnetic
•   Paramagnetic
•  Ferromagnetic
•  None of these

Solution
Water is dia-magnetic.

Q84. The ratio of magnetic moments of two bar magnets is 13∶5. These magnets held together in a vibration magnetometer oscillate with 15 oscillations per minute in earth’s magnetic field with like poles together. What will be the frequency of oscillations of system if unlike poles are together

•  10 oscillations/min
•  15 oscillations/min
•  12 oscillations/min
•  75/13 oscillations/min

Solution
                       

Q85.Curie temperature is the one above which

•  Paramagnetic substance changes of ferromagnetic
•  Paramagnetic changes to diamagnetic
•  Diamagnetic changes to paramagnetic
•  Ferromagnetic changes to paramagnetic

Solution
  The curie temperature or curie point of a ferromagnetic material is the temperature above which it looses its characteristic ferromagnetic ability to possess a net magnetization in the absence of an external magnetic field. Hence, above curie temperature material is purely paramagnetic.

Q86. Time period for a magnet is T. If it is divided in four equal parts along its axis and perpendicular to its axis as shown then time period for each part will be

                                   

•  4T
•  T/2
• T/4
•  T

Solution
                        

Q87.A tangent galvanometer is connected directly to an ideal battery. If the number of turns in the coil is doubled, the deflection will

•  Increase
•  Decrease
•  Remain unchanged
•  Either increase or decrease

Solution
                         

Q88.Curie-Weiss law is obeyed by iron

•  At Curie temperature only
•  At all temperatures
•  Below Curie temperature
•  Above Curie temperature

Solution
Iron is a ferromagnetic substance and ferromagnetic substance obeys Curie-Weiss law above its Curie temperature.

Q89.The susceptibility of a paramagnetic material is K at 27℃. At what temperature will its susceptibility be K/2?

•  600℃
•  287℃
•  54℃
•  327℃

Solution
                       

Q90. Two bar magnets with magnetic moments 2 M and M are fastened together at right angles to each other at their centres to form a crossed system, which can rotate freely about a vertical axis through the centre. The crossed system sets in earth’s magnetic field with magnet having magnetic moment 2M making an angle θ with the magnetic meridian such that

•  θ=tan^-1⁡(1/√3)
•  θ=tan^-1⁡(√3)
•  θ=tan^-1⁡(1/2)
• θ=tan^-1⁡(3/4)

Solution