Magnetic Dip

Q. At a certain place, the horizontal component of earth's magnetic field is $\sqrt{3}$ times the vertical component. The angle of dip at that place is

1. ${60}^{\circ }$
2. ${90}^{\circ }$
3. ${30}^{\circ }$
4. ${45}^{\circ }$

Q.

If ${\theta }_1$and ${\theta }_2$ be the apparent angles of dip observed in two vertical planes at right angles to each other, then the true angle of dip$\left(\theta \right)$ is given by ________

1. ${\tan }^2\theta ={\tan }^2{\theta }_1+{\tan }^2{\theta }_2$

2. $co{t}^2\theta =co{t}^2{\theta }_1-co{t}^2{\theta }_2$

3. ${\tan }^2\theta ={\tan }^2{\theta }_1-{\tan }^2{\theta }_2$

4. $co{t}^2\theta =co{t}^2{\theta }_1+co{t}^2{\theta }_2$

Q. The vertical component of earth's magnetic field is zero at or The earth's magnetic field always has a vertical component except at the

1. Geographical poles
2. Every place
3. Magnetic equator
4. Magnetic poles

Q. If the angles of dip at two places are ${30}^{\circ }$ and ${45}^{\circ }$ respectively, then the ratio of horizontal components of earth's magnetic field at the two places will be

1. $\sqrt{3}:\sqrt{2}$
2. $1:\sqrt{2}$
3. $1:\sqrt{3}$
4. $1:2$

Q.

A magnetic needle is free to rotate in a vertical plane which makes an angle of ${60}^0$ with the magnetic meridian. If the needle stays in a direction making an angle of tan ${}^{-1}\left(\frac{2}{\sqrt{3}}\right)$ with the horizontal, what would be the dip at that place ?

Q.

The magnetic needle of a tangent galvanometer is deflected at an angle $30$ due to a magnet. The horizontal component of the earths magnetic field$0.34\times {10}^{-4}T$ is along the plane of the coil. The magnetic intensity is:

Q.

A magnetic compass needle oscillates $30$ times per minute at a place where the dip is $45°$, and $40$ times per minute where the dip is $30º$. If B1 and B2 are respectively the total magnetic field due to the earth at the two places, then the ratio B₁/ B₂ is best given by:

1. $1.8$

2. $2.2$

3. $0.7$

4. $3.6$

Q.

What are the magnetic elements of the earths magnetic field?

Q. At a place, if the earth’s horizontal and vertical components of magnetic fields are equal, then the angle of dip (in degrees) will be

Q. The earth’s magnetic field at a certain place has a horizontal component 0.3 gauss and the total strength 0.5 gauss. The angle of dip is ${\tan }^{-1}\left(\frac{x}{y}\right)$. Find (x+y).

Q.

The angle of dip at a place is $\delta$. If the dip is measured in a plane making an angle $\theta$ with the magnetic meridian, the apparent angle of dip ${\delta }_1$ will be :

Q.

The needle of a dip circle shows an apparent dip of ${45}^0$ in a particular position and ${53}^0$ when the circle is rotated through ${90}^0$. Find the true dip.

Q. A dip circle is so set that its needle moves freely in the magnetic meridian. In this position, the angle of dip is ${40}^o$. now the dip circle is rotated so that the plane in which the needle moves makes an angle of ${30}^o$ with the magnetic meridian. In this position, the needle will dip by an angle.

1. ${30}^o$
2. ${40}^o$
3. more than ${40}^o$
4. less than ${40}^o$

Q. A dip needle vibrates in the vertical plane perpendicular to the magnetic meridian. The time period of vibration is found to be $2\text{sec}$. The same needle is then allowed to vibrate in the horizontal plane and the time period is again found to be $2\text{sec}$. Then the angle of dip is

1. $0^{\circ }$
2. ${30}^{\circ }$
3. ${45}^{\circ }$
4. ${90}^{\circ }$

Q. An electric dipole of length $10\text{cm}$ having charges $6\times {10}^{-3}\text{C}$ is placed at ${60}^{\circ }$ with respect to a uniform electric field. If it experiences a torque of $3\sqrt{3}\text{N-m}$, then the magnitude of electric field is

1. $3\times {10}^4\text{N/C}$
2. $4\times {10}^4\text{N/C}$
3. $1\times {10}^4\text{N/C}$
4. $2\times {10}^4\text{N/C}$

Q. At a location, vertical component of earth’s magnetic field is $1.6\times {10}^{-5}\text{T}$. If dip angle at that location is ${37}^{\circ }$, then find the magnitude of magnetic field at that point.

Q.

What is the angle of dip?

Q. The horizontal and vertical components of magnetic field of earth are same at some place on the surface of Earth. The magnetic dip angle at this place will be __________.

1. ${90}^o$
2. ${30}^o$
3. $0^o$
4. ${45}^o$

Q. A long straight horizontal cable carries a current of $2.5\text{A}$ in the direction ${10}^{\circ }$ south of west to ${10}^{\circ }$ north of east. The magnetic meridian of the place happens to be ${10}^{\circ }$ west of the geographic meridian. The earth's magnetic field at the location is $0.33\text{G}$, and the angle of dip is zero. Then neutral points lie on a straight line (ignore the thickness of the cable).

1. perpendicular to the cable, below the plane of paper at a perpendicular distance of $1.51\text{cm}.$
2. parallel to the cable at a perpendicular distance of $3.02\text{cm}$.
3. perpendicular to the cable at a perpendicular distance of $3.02\text{cm}$.
4. parallel to the cable, above the plane of paper at a perpendicular distance of $1.51\text{cm}$.

Q.

The magnetic field due to the earth has a horizontal component of $26\mu$ T at a place where the dip is ${60}^0$. Find the vertical component and the magnitude of the field.

Q. At a certain place, the angle of dip ${30}^o$ and the horizontal component of earth's magnetic field is $0.50$ oerested.The earth's total magnetic field (in oerested) is

1. $1$
2. $\frac{1}{\sqrt{3}}$
3. $\frac{1}{2}$
4. $\sqrt{3}$

Q. A dip circle lies initially in the magnetic meridian. If it is now rotated through angle $\theta$ in the horizontal plane, then tangent of the angle of dip is changed in the ratio

1. $1:\cos \theta$
2. $\cos \theta :1$
3. $1:\sin \theta$
4. $\sin \theta :1$

Q.

If we place a bar magnet in the magnetic meridian with its north pole towards geographical North, the neutral point will be

1.on the axial of the magnet

2.on the equatorial line line of magnet

3.at 45 with the axial line

4. At 45 with equatorial line

Q. A dip placed in a plane which is perpendicular to magnetic meridian will remain

1. Parallel to surface of earth
2. At angle ${11.2}^{\circ }$ with surface of earth
3. At angle ${11.2}^{\circ }$ with vertical
4. Vertical

Q. What is the magnetic field at point $\text{P}$ if $\text{AP}$ is making an angle ${15}^{\circ }$ as shown in the figure.

1. $\frac{{\mu }_0}{4\pi }\frac{I}{2a}[\sqrt{3}-\sqrt{2}]$
2. $\frac{{\mu }_0}{2\pi }\frac{I}{a}[\sqrt{3}-\sqrt{2}]$
3. $\frac{{\mu }_0}{\pi }\frac{I}{a}[\sqrt{3}-\sqrt{2}]$
4. none of these

Q. The horizontal component of earth's magnetic field at a place is $\frac{1}{\sqrt{3}}$ times the vertical component. Determine the angle of dip at that place.

Q. A magnetic needle freed to rotate around a fixed vertical plane stay at an angle ${60}^0$ with the horizontal . If the dip at that place is ${37}^0$, find the angle of the fixed vertical plane with the meridian.

1. $\theta ={\cos }^{-1}\left(\frac{\sqrt{3}}{4}\right)$
2. $\theta ={\cos }^{-1}\frac{\sqrt{3}}{5}$
3. $\theta ={\cos }^{-1}\frac{2}{3}$
4. $\theta ={\cos }^{-1}\frac{1}{\sqrt{3}}$

Q. If a dip circle is placed in a vertical plane at an angle of ${30}^{\underset{–}{o}}$ to the magnetic meridian, the dip needle makes an angle of ${45}^{\underset{–}{o}}$ with the horizontal. The real dip at that place is?

1. ${\tan }^{-1}\left(\sqrt{3}/2\right)$
2. ${\tan }^{-1}\left(\sqrt{3}\right)$
3. ${\tan }^{-1}\left(\sqrt{3}/\sqrt{2}\right)$
4. ${\tan }^{-1}\left(2/\sqrt{3}\right)$

Q. In a physics lab, we took two readings of dip angle by dip circle, in two readings planes of dip circle are mutually perpendicular, then ratio of vertical & horizontal component of field the to earth in lab is (reading 1 = ${45}^0$ reading 2 = ${60}^0$)

1. $co{t}^{-1}\left\{\frac{4}{3}\right\}$
2. $co{t}^{-1}\left\{\sqrt{\frac{7}{3}}\right\}$
3. $co{t}^{-1}\left\{\sqrt{\frac{4}{3}}\right\}$
4. $co{t}^{-1}\left\{\frac{7}{3}\right\}$

Q.

If a magnet is suspended at an angle 30${}^0$ to the magnetic meridian, the dip needle makes an angle of ${60}^o$ with the horizontal. The true value of dip is :

1. $ta{n}^{-1}\left(2/3\right)$
2. $ta{n}^{-1}\left(3/2\right)$
3. $ta{n}^{-1}\left(3\right)$
4. $ta{n}^{-1}\left(2\right)$