154496
A flexible wire bent in the form of a circle is placed in a uniform magnetic field, such that the field is perpendicular to the plane of the coil. The radius of the coil changes as shown. The graph of magnitude of induced emf in the coil is represented by
1
2
3
4
Explanation:
B Magnetic field is uniform thus, the flux is changed just because of the change in radius of the coil. If the radius of the coil is constant then the induced emf is zero and if it varies then it has some value. From the figure, radius from a to $b$ doesn't change, so emf induced is zero, from $\mathrm{b}$ to $\mathrm{c}$ the radius increased linearly, so the emf is constant and from $\mathrm{c}$ to $\mathrm{d}$ it is again zero.
AP EAMCET-03.09.2021
Electro Magnetic Induction
154497
Assertion (A): Magnetic flux is a vector quantity Reason (R): Value of magnetic flux can be positive negative or zero.
1 Both $\mathrm{A}$ and $\mathrm{R}$ are true and $\mathrm{R}$ is a correct explanation for $\mathrm{A}$
2 Both $\mathrm{A}$ and $\mathrm{R}$ are true but $\mathrm{R}$ is not a correct explanation for $\mathrm{A}$
3 A is true, $\mathrm{R}$ is false
4 A is false, $R$ is true
Explanation:
D The magnetic flux is a scalar quantity and the value of magnetic flux can be positive negative or zero.
AP EAMCET-20.08.2021
Electro Magnetic Induction
154506
A coil of ' $n$ ' turns and resistance ' $R$ ' $\Omega$ is connected in series with a resistance $\frac{R}{2}$. The combination is moved for time ' $t$ ' second through magnetic flux $\phi_{1}$ to $\phi_{2}$. The induced current in the circuit is
D When a coil of $\mathrm{n}$ turns moves through a magnetic flux from $\phi_{1}$ to $\phi_{2}$, then emf induced in the coil is $\varepsilon=-\mathrm{n} \frac{\mathrm{d} \phi}{\mathrm{dt}}=\frac{-\mathrm{n}\left(\phi_{2}-\phi_{1}\right)}{\mathrm{t}}=\frac{\mathrm{n}\left(\phi_{1}-\phi_{2}\right)}{\mathrm{t}}$ As resistance of coil $\mathrm{R}$ and $\frac{\mathrm{R}}{2}$ are in series. So, equivalent resistance is $\mathrm{R}_{\text {eq }}=\mathrm{R}+\frac{\mathrm{R}}{2}=\frac{3 \mathrm{R}}{2}$ The induced current in the circuit is, $I=\frac{\varepsilon}{R_{e q}}=\frac{n\left(\phi_{1}-\phi_{2}\right)}{t} \times \frac{2}{3 R}$ $I=\frac{2 n\left(\phi_{1}-\phi_{2}\right)}{3 R t}$
MHT-CET 2020
Electro Magnetic Induction
154508
The coil having 1000 turns \& Area of $0.10 \mathrm{~m}^{2}$ rotates at half a revolution per second $\&$ it is placed in a uniform magnetic field of $0.01 \mathrm{~T}$ perpendiculars to the axis of rotation of coil. Then max emf voltage generated in coil is V.
154496
A flexible wire bent in the form of a circle is placed in a uniform magnetic field, such that the field is perpendicular to the plane of the coil. The radius of the coil changes as shown. The graph of magnitude of induced emf in the coil is represented by
1
2
3
4
Explanation:
B Magnetic field is uniform thus, the flux is changed just because of the change in radius of the coil. If the radius of the coil is constant then the induced emf is zero and if it varies then it has some value. From the figure, radius from a to $b$ doesn't change, so emf induced is zero, from $\mathrm{b}$ to $\mathrm{c}$ the radius increased linearly, so the emf is constant and from $\mathrm{c}$ to $\mathrm{d}$ it is again zero.
AP EAMCET-03.09.2021
Electro Magnetic Induction
154497
Assertion (A): Magnetic flux is a vector quantity Reason (R): Value of magnetic flux can be positive negative or zero.
1 Both $\mathrm{A}$ and $\mathrm{R}$ are true and $\mathrm{R}$ is a correct explanation for $\mathrm{A}$
2 Both $\mathrm{A}$ and $\mathrm{R}$ are true but $\mathrm{R}$ is not a correct explanation for $\mathrm{A}$
3 A is true, $\mathrm{R}$ is false
4 A is false, $R$ is true
Explanation:
D The magnetic flux is a scalar quantity and the value of magnetic flux can be positive negative or zero.
AP EAMCET-20.08.2021
Electro Magnetic Induction
154506
A coil of ' $n$ ' turns and resistance ' $R$ ' $\Omega$ is connected in series with a resistance $\frac{R}{2}$. The combination is moved for time ' $t$ ' second through magnetic flux $\phi_{1}$ to $\phi_{2}$. The induced current in the circuit is
D When a coil of $\mathrm{n}$ turns moves through a magnetic flux from $\phi_{1}$ to $\phi_{2}$, then emf induced in the coil is $\varepsilon=-\mathrm{n} \frac{\mathrm{d} \phi}{\mathrm{dt}}=\frac{-\mathrm{n}\left(\phi_{2}-\phi_{1}\right)}{\mathrm{t}}=\frac{\mathrm{n}\left(\phi_{1}-\phi_{2}\right)}{\mathrm{t}}$ As resistance of coil $\mathrm{R}$ and $\frac{\mathrm{R}}{2}$ are in series. So, equivalent resistance is $\mathrm{R}_{\text {eq }}=\mathrm{R}+\frac{\mathrm{R}}{2}=\frac{3 \mathrm{R}}{2}$ The induced current in the circuit is, $I=\frac{\varepsilon}{R_{e q}}=\frac{n\left(\phi_{1}-\phi_{2}\right)}{t} \times \frac{2}{3 R}$ $I=\frac{2 n\left(\phi_{1}-\phi_{2}\right)}{3 R t}$
MHT-CET 2020
Electro Magnetic Induction
154508
The coil having 1000 turns \& Area of $0.10 \mathrm{~m}^{2}$ rotates at half a revolution per second $\&$ it is placed in a uniform magnetic field of $0.01 \mathrm{~T}$ perpendiculars to the axis of rotation of coil. Then max emf voltage generated in coil is V.
154496
A flexible wire bent in the form of a circle is placed in a uniform magnetic field, such that the field is perpendicular to the plane of the coil. The radius of the coil changes as shown. The graph of magnitude of induced emf in the coil is represented by
1
2
3
4
Explanation:
B Magnetic field is uniform thus, the flux is changed just because of the change in radius of the coil. If the radius of the coil is constant then the induced emf is zero and if it varies then it has some value. From the figure, radius from a to $b$ doesn't change, so emf induced is zero, from $\mathrm{b}$ to $\mathrm{c}$ the radius increased linearly, so the emf is constant and from $\mathrm{c}$ to $\mathrm{d}$ it is again zero.
AP EAMCET-03.09.2021
Electro Magnetic Induction
154497
Assertion (A): Magnetic flux is a vector quantity Reason (R): Value of magnetic flux can be positive negative or zero.
1 Both $\mathrm{A}$ and $\mathrm{R}$ are true and $\mathrm{R}$ is a correct explanation for $\mathrm{A}$
2 Both $\mathrm{A}$ and $\mathrm{R}$ are true but $\mathrm{R}$ is not a correct explanation for $\mathrm{A}$
3 A is true, $\mathrm{R}$ is false
4 A is false, $R$ is true
Explanation:
D The magnetic flux is a scalar quantity and the value of magnetic flux can be positive negative or zero.
AP EAMCET-20.08.2021
Electro Magnetic Induction
154506
A coil of ' $n$ ' turns and resistance ' $R$ ' $\Omega$ is connected in series with a resistance $\frac{R}{2}$. The combination is moved for time ' $t$ ' second through magnetic flux $\phi_{1}$ to $\phi_{2}$. The induced current in the circuit is
D When a coil of $\mathrm{n}$ turns moves through a magnetic flux from $\phi_{1}$ to $\phi_{2}$, then emf induced in the coil is $\varepsilon=-\mathrm{n} \frac{\mathrm{d} \phi}{\mathrm{dt}}=\frac{-\mathrm{n}\left(\phi_{2}-\phi_{1}\right)}{\mathrm{t}}=\frac{\mathrm{n}\left(\phi_{1}-\phi_{2}\right)}{\mathrm{t}}$ As resistance of coil $\mathrm{R}$ and $\frac{\mathrm{R}}{2}$ are in series. So, equivalent resistance is $\mathrm{R}_{\text {eq }}=\mathrm{R}+\frac{\mathrm{R}}{2}=\frac{3 \mathrm{R}}{2}$ The induced current in the circuit is, $I=\frac{\varepsilon}{R_{e q}}=\frac{n\left(\phi_{1}-\phi_{2}\right)}{t} \times \frac{2}{3 R}$ $I=\frac{2 n\left(\phi_{1}-\phi_{2}\right)}{3 R t}$
MHT-CET 2020
Electro Magnetic Induction
154508
The coil having 1000 turns \& Area of $0.10 \mathrm{~m}^{2}$ rotates at half a revolution per second $\&$ it is placed in a uniform magnetic field of $0.01 \mathrm{~T}$ perpendiculars to the axis of rotation of coil. Then max emf voltage generated in coil is V.
154496
A flexible wire bent in the form of a circle is placed in a uniform magnetic field, such that the field is perpendicular to the plane of the coil. The radius of the coil changes as shown. The graph of magnitude of induced emf in the coil is represented by
1
2
3
4
Explanation:
B Magnetic field is uniform thus, the flux is changed just because of the change in radius of the coil. If the radius of the coil is constant then the induced emf is zero and if it varies then it has some value. From the figure, radius from a to $b$ doesn't change, so emf induced is zero, from $\mathrm{b}$ to $\mathrm{c}$ the radius increased linearly, so the emf is constant and from $\mathrm{c}$ to $\mathrm{d}$ it is again zero.
AP EAMCET-03.09.2021
Electro Magnetic Induction
154497
Assertion (A): Magnetic flux is a vector quantity Reason (R): Value of magnetic flux can be positive negative or zero.
1 Both $\mathrm{A}$ and $\mathrm{R}$ are true and $\mathrm{R}$ is a correct explanation for $\mathrm{A}$
2 Both $\mathrm{A}$ and $\mathrm{R}$ are true but $\mathrm{R}$ is not a correct explanation for $\mathrm{A}$
3 A is true, $\mathrm{R}$ is false
4 A is false, $R$ is true
Explanation:
D The magnetic flux is a scalar quantity and the value of magnetic flux can be positive negative or zero.
AP EAMCET-20.08.2021
Electro Magnetic Induction
154506
A coil of ' $n$ ' turns and resistance ' $R$ ' $\Omega$ is connected in series with a resistance $\frac{R}{2}$. The combination is moved for time ' $t$ ' second through magnetic flux $\phi_{1}$ to $\phi_{2}$. The induced current in the circuit is
D When a coil of $\mathrm{n}$ turns moves through a magnetic flux from $\phi_{1}$ to $\phi_{2}$, then emf induced in the coil is $\varepsilon=-\mathrm{n} \frac{\mathrm{d} \phi}{\mathrm{dt}}=\frac{-\mathrm{n}\left(\phi_{2}-\phi_{1}\right)}{\mathrm{t}}=\frac{\mathrm{n}\left(\phi_{1}-\phi_{2}\right)}{\mathrm{t}}$ As resistance of coil $\mathrm{R}$ and $\frac{\mathrm{R}}{2}$ are in series. So, equivalent resistance is $\mathrm{R}_{\text {eq }}=\mathrm{R}+\frac{\mathrm{R}}{2}=\frac{3 \mathrm{R}}{2}$ The induced current in the circuit is, $I=\frac{\varepsilon}{R_{e q}}=\frac{n\left(\phi_{1}-\phi_{2}\right)}{t} \times \frac{2}{3 R}$ $I=\frac{2 n\left(\phi_{1}-\phi_{2}\right)}{3 R t}$
MHT-CET 2020
Electro Magnetic Induction
154508
The coil having 1000 turns \& Area of $0.10 \mathrm{~m}^{2}$ rotates at half a revolution per second $\&$ it is placed in a uniform magnetic field of $0.01 \mathrm{~T}$ perpendiculars to the axis of rotation of coil. Then max emf voltage generated in coil is V.
