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All questions of Magnetic Forces for Grade 8 Exam
When the direction of current through the conductor is reversed, the direction of- a)force is also reversed
- b)force remains same
- c)electromagnetic field is reversed
- d)electric field is also reversed
Correct answer is option 'A'. Can you explain this answer?
When the direction of current through the conductor is reversed, the direction of
a)
force is also reversed
b)
force remains same
c)
electromagnetic field is reversed
d)
electric field is also reversed
|
Drnitin Gopale answered |
Stretch out your hand as per Fleming left-hand rule and then tilt your hand upside down. You can see that the direction of mag field is the same, but the direction of current has reversed as per the question. also, the thumb goes downwards i.e opposite to initial direction. hence, we can see that the direction of force has been reversed.
Assertion (A): The direction of force on a current-carrying conductor placed in a magnetic field depends on the direction of both the current and the magnetic field.Reason (R): When the direction of the current through the conductor is perpendicular to the direction of the magnetic field, the force experienced by the conductor is at its maximum.- a)If both Assertion and Reason are true and Reason is the correct explanation of Assertion
- b)If both Assertion and Reason are true but Reason is not the correct explanation of Assertion
- c)If Assertion is true but Reason is false
- d)If both Assertion and Reason are false
Correct answer is option 'B'. Can you explain this answer?
Assertion (A): The direction of force on a current-carrying conductor placed in a magnetic field depends on the direction of both the current and the magnetic field.
Reason (R): When the direction of the current through the conductor is perpendicular to the direction of the magnetic field, the force experienced by the conductor is at its maximum.
a)
If both Assertion and Reason are true and Reason is the correct explanation of Assertion
b)
If both Assertion and Reason are true but Reason is not the correct explanation of Assertion
c)
If Assertion is true but Reason is false
d)
If both Assertion and Reason are false
|
Kamna Science Academy answered |
- The assertion that the force on a current-carrying conductor in a magnetic field depends on the directions of both the current and the magnetic field is correct. This relationship is described by the right-hand rule for the force on a current-carrying conductor in a magnetic field.
- The reason that the force is maximum when the current is perpendicular to the magnetic field is also correct. This is a fundamental principle of electromagnetism.
- However, the reason does not directly explain why the assertion is true. While it is true that the force is maximum when the current is perpendicular to the magnetic field, this fact alone does not fully explain the dependence of the force on the directions of both the current and the magnetic field. Hence, Option B is the correct answer.
What happens to the direction of the force on a current-carrying conductor when the direction of the current is reversed, while the magnetic field remains unchanged?- a)The direction of the force remains the same.
- b)The direction of the force is reversed.
- c)The magnitude of the force is doubled.
- d)The force becomes zero.
Correct answer is option 'B'. Can you explain this answer?
a)
The direction of the force remains the same.
b)
The direction of the force is reversed.
c)
The magnitude of the force is doubled.
d)
The force becomes zero.
|
Ciel Knowledge answered |
According to Fleming's left-hand rule, if the direction of the current is reversed while keeping the magnetic field unchanged, the direction of the force on the conductor is also reversed.
The magnetic field inside a long straight solenoid carrying current _____.- a)is zero
- b)decreases as we move towards its end
- c)increases as we move towards its end
- d)is the same at all points
Correct answer is option 'D'. Can you explain this answer?
The magnetic field inside a long straight solenoid carrying current _____.
a)
is zero
b)
decreases as we move towards its end
c)
increases as we move towards its end
d)
is the same at all points
|
Janani Yadav answered |
Understanding Magnetic Field in a Solenoid
The magnetic field inside a long straight solenoid is a fundamental concept in electromagnetism.
Uniform Magnetic Field
- Inside a long solenoid, the magnetic field lines are parallel and evenly spaced.
- This indicates that the magnetic field strength is uniform throughout the interior of the solenoid.
Factors Affecting the Magnetic Field
- The magnetic field inside a solenoid depends on:
- The number of turns per unit length (n).
- The current (I) flowing through the solenoid.
- The formula for the magnetic field (B) inside a solenoid is given by:
B = μ₀nI
where μ₀ is the permeability of free space.
Behavior at the Ends
- At the ends of a solenoid, the magnetic field does not decrease; instead, it remains approximately constant inside.
- However, outside the solenoid, the field lines diverge, leading to a much weaker magnetic field.
Conclusion
- Since the magnetic field remains consistent at all points within the long solenoid and does not vary with position along its length, the correct answer is indeed option 'D': the magnetic field inside a long straight solenoid carrying current is the same at all points.
This property is crucial for applications in electromagnets, inductors, and various electronic devices, making the solenoid an essential component in physics and engineering.
The magnetic field inside a long straight solenoid is a fundamental concept in electromagnetism.
Uniform Magnetic Field
- Inside a long solenoid, the magnetic field lines are parallel and evenly spaced.
- This indicates that the magnetic field strength is uniform throughout the interior of the solenoid.
Factors Affecting the Magnetic Field
- The magnetic field inside a solenoid depends on:
- The number of turns per unit length (n).
- The current (I) flowing through the solenoid.
- The formula for the magnetic field (B) inside a solenoid is given by:
B = μ₀nI
where μ₀ is the permeability of free space.
Behavior at the Ends
- At the ends of a solenoid, the magnetic field does not decrease; instead, it remains approximately constant inside.
- However, outside the solenoid, the field lines diverge, leading to a much weaker magnetic field.
Conclusion
- Since the magnetic field remains consistent at all points within the long solenoid and does not vary with position along its length, the correct answer is indeed option 'D': the magnetic field inside a long straight solenoid carrying current is the same at all points.
This property is crucial for applications in electromagnets, inductors, and various electronic devices, making the solenoid an essential component in physics and engineering.
If a current-carrying conductor is placed in a uniform magnetic field and oriented parallel to the magnetic field lines, what happens to the force on the conductor?- a)The force is at its maximum.
- b)The force is zero.
- c)The force is doubled.
- d)The force becomes perpendicular to the field.
Correct answer is option 'B'. Can you explain this answer?
If a current-carrying conductor is placed in a uniform magnetic field and oriented parallel to the magnetic field lines, what happens to the force on the conductor?
a)
The force is at its maximum.
b)
The force is zero.
c)
The force is doubled.
d)
The force becomes perpendicular to the field.
|
Top Rankers answered |
When a current-carrying conductor is oriented parallel to the magnetic field lines, the force experienced by the conductor is zero. This is because the force on the conductor is given by F=BILsinθ, where θ is the angle between the direction of the current and the magnetic field. When θ is 0 degrees (parallel), sinθ is zero, resulting in no force.
A current-carrying rod experiences a force perpendicular to its length and the ______ field.- a)Electric
- b)Magnetic
- c)Gravitational
- d)Static
Correct answer is option 'B'. Can you explain this answer?
A current-carrying rod experiences a force perpendicular to its length and the ______ field.
a)
Electric
b)
Magnetic
c)
Gravitational
d)
Static
|
EduRev NEET answered |
A current-carrying rod experiences a force perpendicular to its length and the magnetic field, as described by the interaction between current and magnetic fields in electromagnetism.
Which of the following statements is true about the magnetic field inside a long, straight solenoid carrying current?- a)The magnetic field is strongest at the ends of the solenoid.
- b)The magnetic field inside the solenoid is uniform and parallel to the axis.
- c)The magnetic field inside the solenoid is zero.
- d)The magnetic field inside the solenoid fluctuates randomly.
Correct answer is option 'B'. Can you explain this answer?
a)
The magnetic field is strongest at the ends of the solenoid.
b)
The magnetic field inside the solenoid is uniform and parallel to the axis.
c)
The magnetic field inside the solenoid is zero.
d)
The magnetic field inside the solenoid fluctuates randomly.
|
Nk Classes answered |
Inside a long, straight solenoid carrying current, the magnetic field is uniform and parallel to the axis of the solenoid. This uniformity is due to the fact that the magnetic field lines are parallel and closely spaced inside the solenoid.
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