A circular loop carrying a current is replaced by an equivalent magnetic dipole. A point on the axis of the loop is in: 

A circular loop carrying a current is replaced by an equivalent magnetic dipole. A point on the loop is in

1.  end-on position

2.  broadside-on position

3.  both

4.  none

When a current in a circular loop is equivalently replaced by a magnetic dipole:

Let r be the distance of a point on the axis of a bar magnet from its centre. The magnetic field at such a point is proportional to

1.   \(1 \over r\)

2.    \(1 \over r^2\)

3.     \(1 \over r^3\)

4.   none of these

Let \(r\) be the distance of a point on the axis of a magnetic dipole from its centre. The magnetic field at such a point is proportional to:
1. \(\dfrac 1 r\)
2. \(\dfrac 1 {r^2}\)
3. \(\dfrac 1 {r^3}\)
4. none of these

1. \(\frac{\mu_{\mathrm{0}}}{4 \pi} \frac{\mathrm{M}}{\mathrm{d}^{3}}\)
2. \(\frac{\mu_{0}}{4 \pi} \frac{\sqrt{2} \mathrm{M}}{\mathrm{d}^{3}}\)
3. \(\frac{\mu_{0}}{4 \pi} \frac{2\sqrt{2} \mathrm{M}}{\mathrm{d}^{3}}\)
4. \(\frac{\mu_{\mathrm{0}}}{4 \pi} \frac{\mathrm{2M}}{\mathrm{d}^{3}}\)

A horizontal circular loop carries a current that looks clockwise when viewed from above. It is replaced by an equivalent magnetic dipole consisting of a south pole \(S\) and a north pole \(N.\)

Choose the correct option from the given ones:
1. (a) and (b) only
2. (b) and (d) only
3. (c) and (d) only
4. (a) and (d) only

Choose the correct option: 
1. (a), (b) 
2. (b), (c) 
3. (c), (d) 
4. (a), (d) 

Consider the situation of the previous problem. The directions of the magnetic field due to the dipole are opposite at

(a) P₁ and P₂

(b) Q₁ and Q₂ 

(c) P₁ and Q₁

(d) P₂ and Q₂

Choose the correct option 

1.  (a) , (b) 

2. (b) , (c) 

3. (c) , (d) 

4. (a) , (d)

Previous problem: Consider a magnetic dipole kept in the north-south direction. Let P₁, P₂ Q₁, Q₂ be four points at the same distance from the dipole towards north, south, east and west of the dipole respectively.

To measure the magnetic moment of a bar magnet, one may use

(a) a tangent galvanometer

(b) a deflection galvanometer if the earth’s horizontal field is known

(c) an oscillation magnetometer if the earth’s horizontal field is known

(d) both deflection and oscillation magnetometer if the earth’s horizontal field is not known

Choose the correct option 

1.  (a) , (b) , (c)

2. (b) , (c) , (d)

3. (c) , (d) , (a)

4. (a) , (d) , (b)