JEE Mains · Physics · STD 12 - Magnetism and matter
- JEE Mains 2017
- Medium
- MCQ
A magnetic needle of magnetic moment \(6.7 \times 10^{-2} \) \(Am^2\) and moment of inertia \(7.5 \times 10^{-6}\) \( kgm^2\) is performing simple harmonic oscillations in a magnetic field of \(0.01\ T\). Time taken for \(10\) complete oscillations is.....\(s\)
Pick an option to check your answer.
Answer & Solution
Correct Answer
(A) \(6.65\)
Step-by-step Solution
Detailed explanation
Given : Magnetic moment, \(M=6.7 \times 10^{-2}\, \mathrm{Am}^{2}\)
Magnetic field, \(\mathrm{B}=0.01\, \mathrm{T}\)
Moment of inertia, \(I=7.5 \times 10^{-6}\, \mathrm{Kgm}^{2}\)
\(\text { Using, } T =2 \pi \sqrt{\frac{I}{M B}} \)
\(=2 \pi \sqrt{\frac{7.5 \times 10^{-6}}{6.7 \times 10^{-2} \times 0.01}}=\frac{2 \pi}{10} \times 1.06\, s\)
Time taken for \(10\) complete oscillations
\(t=10\, T=2 \pi \times 1.06 \)
\(=6.6568 \approx 6.65\, \mathrm{s}\)
More questions from Physics
- Two \(10 \; cm\) long, straight wires, each carrying a current of \(5 \; A\) are kept parallel to each other. If each wire experienced a force of \(10^{-5} \; N\), then separation between the wires is \(\dots \; cm\).JEE Mains 2022 Medium
- A zener diode with 5 V zener voltage is used to regulate an unregulated dc voltage input of 25 V. For a \(400 \Omega\) resistor connected in series, the zener current is found to be 4 times load current. The load current \(\left(I_L\right)\) and load resistance \(\left(R_{\mathrm{L}}\right)\) are :JEE Mains 2025 Easy
- A thin rod having a length of \(1\; m\) and area of cross-section \(3 \times 10^{-6}\,m ^2\) is suspended vertically from one end. The rod is cooled from \(210^{\circ}\,C\) to \(160^{\circ}\,C\). After cooling, a mass \(M\) is attached at the lower end of the rod such that the length of rod again becomes \(1\,m\). Young's modulus and coefficient of linear expansion of the rod are \(2 \times 10^{11} Nm ^{-2}\) and \(2 \times 10^{-5} K ^{-1}\), respectively. The value of \(M\) is \(.......kg .\left(\right.\) Take \(\left.g=10\,m s ^{-2}\right)\)JEE Mains 2023 Medium
- Two ions of masses \(4 \,{amu}\) and \(16\, amu\) have charges \(+2 {e}\) and \(+3 {e}\) respectively. These ions pass through the region of constant perpendicular magnetic field. The kinetic energy of both ions is same. Then :JEE Mains 2021 Hard
- Figure shows elliptical path \(abcd\) of a planet around the sun \(S\) such that the area of triangle \(csa\) is \(\frac {1}{4}\) the area of the ellipse. (See figure) With \(db\) as the semimajor axis, and \(ca\) as the semiminor axis. If \(t_1\) is the time taken for planet to go over path \(abc\) and \(t_2\) for path taken over \(cda\) then
JEE Mains 2016 Hard - In a Frank-hertz experiment, an electron of energy \(5.6\,eV\) passes through mercury vapour and emerges with an energy \(0.7\,eV.\) The minimum wavelength of photons emitted by mercury atoms is close to ............. \(nm\)JEE Mains 2019 Medium
More PYQs from JEE Mains
- A small toy starts moving from the position of rest under a constant acceleration. If it travels a distance of \(10 \,m\) in \(t \;s ,\) the distance travelled by the toy in the next \(t s\) will be .........\(m\)JEE Mains 2022 Medium
- A charged particle carrying charge \(1\,\mu C\) is moving with velocity \((2 \hat{ i }+3 \hat{ j }+4 \hat{ k })\, ms ^{-1} .\) If an external magnetic field of \((5 \hat{ i }+3 \hat{ j }-6 \hat{ k }) \times 10^{-3}\, T\) exists in the region where the particle is moving then the force on the particle is \(\overline{ F } \times 10^{-9} N\). The vector \(\overrightarrow{ F }\) is :JEE Mains 2020 Medium
- Given below are two statements : Statement \(I\) : When speed of liquid is zero everywhere, pressure difference at any two points depends on equation \(\mathrm{P}_1-\mathrm{P}_2=\rho \mathrm{g}\left(\mathrm{h}_2-\mathrm{h}_1\right)\) Statement \(II\) : In ventury tube shown \(2 \mathrm{gh}=v_1^2-v_2^2\) In the light of the above statements, choose the most appropriate answer from the options given below.
JEE Mains 2024 Hard - A cylindrical container of volume \(4.0 \times 10^{-3} \,{m}^{3}\) contains one mole of hydrogen and two moles of carbon dioxide. Assume the temperature of the mixture is \(400 \,{K}\) The pressure of the mixture of gases is: [Take gas constant as \(8.3\, {J} {mol}^{-1} {K}^{-1}\)]JEE Mains 2021 Medium
- Given below are two statements: one is labelled as Assertion \(A\) and the other is labelled as Reason \(R\). Assertion \(A :\) The escape velocities of planet \(A\) and \(B\) are same. But \(A\) and \(B\) are of unequal mass. Reason \(R :\) The product of their mass and radius must be same, \(M _{1} R _{1}= M _{2} R _{2}\) In the light of the above statements, choose the most appropriate answer from the options given belowJEE Mains 2021 Medium
- Two satellites \(A\) and \(B\) move round the earth in the same orbit. The mass of \(A\) is twice the mass of \(B\). The quantity which is same for the two satellites will be :JEE Mains 2023 Medium