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PHXII05:MAGNETISM and MATTER

360409 Assertion :
Two short magnets are placed on a cork which floats on water. The magnets are placed such that the axis of one produced bisects the axis of other at right angles. Then, the cork has neither translational nor rotational motion.
Reason :
Net force on the cork is zero
supporting img

1 Both Assertion and Reason are correct and Reason is the correct explanation of Assertion.

2 Both Assertion and Reason are correct but Reason is not the correct explanation of Assertion.

3 Assertion is correct but Reason is incorrect

4 Both Assertion and Reason are incorrect

AIIMS - 2009

PHXII05:MAGNETISM and MATTER

360410 A magnetic needle is kept in a non-uniform magnetic field. It experiences

1 a force only but not a torque

2 a force and torque both

3 a torque only but not a force

4 neither a torque nor a force

PHXII05:MAGNETISM and MATTER

360411 The couple acting on a magnet of length 10 $c m$ and pole strength 15 $A m$ , kept in a field of $B = 2 \times 10^{- 5} T$ , at an angle of is :

1

1.5 \times 10^{- 3} N m

2

1.5 \times 10^{- 5} N m

3

1.5 \times 10^{- 6} N m

4

1.5 \times 10^{- 2} N m

Explanation:

As
$C = M B \sin θ = (m \times 2 l) \times 2 \times 10^{- 5} \sin 30^{\circ}$
$= 15 \times 10 \times 10^{2} \times 10^{- 5} \times \frac{1}{2} = 1.5 \times 10^{- 5} N m$

PHXII05:MAGNETISM and MATTER

360412 A bar magnet of length 0.2 $m$ and pole strength 5 $A m$ is kept in a uniform magnetic induction field of strength $15 w b / m^{- 2}$ making an angle of $30^{\circ}$ with the field. Find the couple acting on it.

1 5.5

N m

2 2.5

N m

3 9.0

N m

4 0.75

N m

Explanation:

Couple acting on a bar magnet of dipole moment $M$ . When placed in a magnetic field, is given by $τ = M B \sin θ$
Where $θ$ is the angle made by the axis of magnet with the direction of field.
Given that $m = 5 A m, 2 l = 0.2 m, θ = 30^{\circ}$ and
$B = 15 W b m^{- 2}$
$∴ τ = M B \sin θ = (m \times 2 ℓ) B \sin θ$
$= 5 \times 0.2 \times 15 \times \frac{1}{2} = 7.5 N m .$

PHXII05:MAGNETISM and MATTER

360409 Assertion :
Two short magnets are placed on a cork which floats on water. The magnets are placed such that the axis of one produced bisects the axis of other at right angles. Then, the cork has neither translational nor rotational motion.
Reason :
Net force on the cork is zero
supporting img

1 Both Assertion and Reason are correct and Reason is the correct explanation of Assertion.

2 Both Assertion and Reason are correct but Reason is not the correct explanation of Assertion.

3 Assertion is correct but Reason is incorrect

4 Both Assertion and Reason are incorrect

AIIMS - 2009

PHXII05:MAGNETISM and MATTER

360410 A magnetic needle is kept in a non-uniform magnetic field. It experiences

1 a force only but not a torque

2 a force and torque both

3 a torque only but not a force

4 neither a torque nor a force

PHXII05:MAGNETISM and MATTER

360411 The couple acting on a magnet of length 10 $c m$ and pole strength 15 $A m$ , kept in a field of $B = 2 \times 10^{- 5} T$ , at an angle of is :

1

1.5 \times 10^{- 3} N m

2

1.5 \times 10^{- 5} N m

3

1.5 \times 10^{- 6} N m

4

1.5 \times 10^{- 2} N m

Explanation:

As
$C = M B \sin θ = (m \times 2 l) \times 2 \times 10^{- 5} \sin 30^{\circ}$
$= 15 \times 10 \times 10^{2} \times 10^{- 5} \times \frac{1}{2} = 1.5 \times 10^{- 5} N m$

PHXII05:MAGNETISM and MATTER

360412 A bar magnet of length 0.2 $m$ and pole strength 5 $A m$ is kept in a uniform magnetic induction field of strength $15 w b / m^{- 2}$ making an angle of $30^{\circ}$ with the field. Find the couple acting on it.

1 5.5

N m

2 2.5

N m

3 9.0

N m

4 0.75

N m

Explanation:

Couple acting on a bar magnet of dipole moment $M$ . When placed in a magnetic field, is given by $τ = M B \sin θ$
Where $θ$ is the angle made by the axis of magnet with the direction of field.
Given that $m = 5 A m, 2 l = 0.2 m, θ = 30^{\circ}$ and
$B = 15 W b m^{- 2}$
$∴ τ = M B \sin θ = (m \times 2 ℓ) B \sin θ$
$= 5 \times 0.2 \times 15 \times \frac{1}{2} = 7.5 N m .$

PHXII05:MAGNETISM and MATTER

360409 Assertion :
Two short magnets are placed on a cork which floats on water. The magnets are placed such that the axis of one produced bisects the axis of other at right angles. Then, the cork has neither translational nor rotational motion.
Reason :
Net force on the cork is zero
supporting img

1 Both Assertion and Reason are correct and Reason is the correct explanation of Assertion.

2 Both Assertion and Reason are correct but Reason is not the correct explanation of Assertion.

3 Assertion is correct but Reason is incorrect

4 Both Assertion and Reason are incorrect

AIIMS - 2009

PHXII05:MAGNETISM and MATTER

360410 A magnetic needle is kept in a non-uniform magnetic field. It experiences

1 a force only but not a torque

2 a force and torque both

3 a torque only but not a force

4 neither a torque nor a force

PHXII05:MAGNETISM and MATTER

360411 The couple acting on a magnet of length 10 $c m$ and pole strength 15 $A m$ , kept in a field of $B = 2 \times 10^{- 5} T$ , at an angle of is :

1

1.5 \times 10^{- 3} N m

2

1.5 \times 10^{- 5} N m

3

1.5 \times 10^{- 6} N m

4

1.5 \times 10^{- 2} N m

Explanation:

As
$C = M B \sin θ = (m \times 2 l) \times 2 \times 10^{- 5} \sin 30^{\circ}$
$= 15 \times 10 \times 10^{2} \times 10^{- 5} \times \frac{1}{2} = 1.5 \times 10^{- 5} N m$

PHXII05:MAGNETISM and MATTER

360412 A bar magnet of length 0.2 $m$ and pole strength 5 $A m$ is kept in a uniform magnetic induction field of strength $15 w b / m^{- 2}$ making an angle of $30^{\circ}$ with the field. Find the couple acting on it.

1 5.5

N m

2 2.5

N m

3 9.0

N m

4 0.75

N m

Explanation:

Couple acting on a bar magnet of dipole moment $M$ . When placed in a magnetic field, is given by $τ = M B \sin θ$
Where $θ$ is the angle made by the axis of magnet with the direction of field.
Given that $m = 5 A m, 2 l = 0.2 m, θ = 30^{\circ}$ and
$B = 15 W b m^{- 2}$
$∴ τ = M B \sin θ = (m \times 2 ℓ) B \sin θ$
$= 5 \times 0.2 \times 15 \times \frac{1}{2} = 7.5 N m .$

PHXII05:MAGNETISM and MATTER

360409 Assertion :
Two short magnets are placed on a cork which floats on water. The magnets are placed such that the axis of one produced bisects the axis of other at right angles. Then, the cork has neither translational nor rotational motion.
Reason :
Net force on the cork is zero
supporting img

1 Both Assertion and Reason are correct and Reason is the correct explanation of Assertion.

2 Both Assertion and Reason are correct but Reason is not the correct explanation of Assertion.

3 Assertion is correct but Reason is incorrect

4 Both Assertion and Reason are incorrect

AIIMS - 2009

PHXII05:MAGNETISM and MATTER

360410 A magnetic needle is kept in a non-uniform magnetic field. It experiences

1 a force only but not a torque

2 a force and torque both

3 a torque only but not a force

4 neither a torque nor a force

PHXII05:MAGNETISM and MATTER

360411 The couple acting on a magnet of length 10 $c m$ and pole strength 15 $A m$ , kept in a field of $B = 2 \times 10^{- 5} T$ , at an angle of is :

1

1.5 \times 10^{- 3} N m

2

1.5 \times 10^{- 5} N m

3

1.5 \times 10^{- 6} N m

4

1.5 \times 10^{- 2} N m

Explanation:

As
$C = M B \sin θ = (m \times 2 l) \times 2 \times 10^{- 5} \sin 30^{\circ}$
$= 15 \times 10 \times 10^{2} \times 10^{- 5} \times \frac{1}{2} = 1.5 \times 10^{- 5} N m$

PHXII05:MAGNETISM and MATTER

360412 A bar magnet of length 0.2 $m$ and pole strength 5 $A m$ is kept in a uniform magnetic induction field of strength $15 w b / m^{- 2}$ making an angle of $30^{\circ}$ with the field. Find the couple acting on it.

1 5.5

N m

2 2.5

N m

3 9.0

N m

4 0.75

N m

Explanation:

Couple acting on a bar magnet of dipole moment $M$ . When placed in a magnetic field, is given by $τ = M B \sin θ$
Where $θ$ is the angle made by the axis of magnet with the direction of field.
Given that $m = 5 A m, 2 l = 0.2 m, θ = 30^{\circ}$ and
$B = 15 W b m^{- 2}$
$∴ τ = M B \sin θ = (m \times 2 ℓ) B \sin θ$
$= 5 \times 0.2 \times 15 \times \frac{1}{2} = 7.5 N m .$