Quiz-17-magnetic-effect-of-current-&-magnetism

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MAGNETISM AND MATTER Quiz-17

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. .

Q1. Susceptibility of ferromagnetic substance is

•  >1
•  <1
•  Zero
•  1

Solution
It is a fact.

Q2. For protecting a sensitive equipment from the external magnetic field, it should be

•  Placed inside an aluminium case
•  Placed inside an iron case
•  Wrapped with insulation around it when passing current through it
•  Surrounded with fine copper sheet

Solution
Concept of magnetic screening

Q3. The plane of a dip circle is set in the geographic meridian and the apparent dip is δ₁. It is then set in a vertical plane perpendicular to the geographic meridian. The apparent dip angle is δ₂. The declination θ at the place is

•  θ= tan^-1(tanδ₁ tan⁡δ₂)
•  θ= tan^-1(tanδ₁+tanδ₂)
•  θ=tan^-1⁡((tanδ₁)/(tanδ₂))
•  θ=tan^-1(tanδ₁-tanδ₂)

Solution
It is a fact.

Q4. Two magnets of same size and mass make respectively 10 and 15 oscillations perminute at certain place. The ratio of their magnetic moments is

•  4∶9
•  9∶4
•  2∶3
•  3∶2

Solution

Q5.The use of study of hysteresis curve for a given material is to estimate the

•  Voltage loss
•  Hysteresis loss
•  Current loss
•  All of these

Solution
 It is a fact.

Q6. The universal property of all substances is

•  Diamagnetism
•  Ferromagnetism
• Paramagnetism
•  All of these

Solution
It is a fact.

Q7.Two identical bar magnets are placed one above the other such that they are mutually perpendicular and bisect each other. The time period of this combination in a horizontal magnetic field is T. The time period of each magnet in the same field is

•  √2T
•  2^1/4T
•  2^1/4T
•  2^1/2T

Solution
Time period of combination 

Q8.Magnetic susceptibility of a diamagnetic substance

•  Decreases with temperature
•  Is not affected by temperature
•  Increases with temperature
•  First increase then decrease with temperature

Solution
Magnetic susceptibility is give as X_m=I/H Large value of X_m implies that the material is more susceptible to the field and hence can be easily magnetized. For diamagnetic substanceX_m is small and negative and is independent of temperature.

Q9.The magnetic field due to a small magnetic dipole of magnetic moment M, at distance r from the centre on the equatorial line is given by (in M.K.S system)

•  μ₀/4π×M/r²
•  μ₀/4π×M/r³
•  μ₀/4π×2M/r²
•  μ₀/4π×2M/r³

Solution
B_equatorial=μ₀/4π M/r³

Q10. A uniform magnetic needle is suspended from its centre by a thread. Its upper end is now loaded with a mass 50 mg, and the needle becomes horizontal. If the strength of each pole is 98.1 ab-amp-cm and g=981 cms^-2, then the vertical component of earth’s magnetic induction is

•  0.50 G
•  0.25 G
•  0.005 G
• 0.05 G

Solution
As shown in figure, mass M=50 mg=50×10^-3 g strength of each pole, m=98.1 ab-amp-cm, g = 981cms^-2,V=?