Concept explainers
In Figure P22.20, the cube is 40.0 cm on each edge. Four straight segments of wire—ab, bc, cd, and da—form a closed loop that carries a current I = 5.00 A in the direction shown. A uniform magnetic field of magnitude B = 0.020 0 T is in the positive y direction. Determine the magnetic force vector on (a) ab, (b) bc, (c) cd, and (d) da. (e) Explain how you could find the force exerted on the fourth of these segments from the forces on the other three, without further calculation involving the magnetic field.
(a)
The magnetic force vector on
Answer to Problem 20P
The magnetic force vector on
Explanation of Solution
Write the expression for the magnetic field in a wire,
Here,
Conclusion:
Substitute
The magnetic force vector on
(b)
The magnetic force vector on
Answer to Problem 20P
The magnetic force vector on
Explanation of Solution
Write the expression for the magnetic field in a wire,
Here,
Conclusion:
Substitute
By Flemings right hand rule, the thumb points towards the
The magnetic force vector on
(c)
The magnetic force vector on
Answer to Problem 20P
The magnetic force vector on
Explanation of Solution
Write the expression for the magnetic field in a wire,
Here,
Write the Pythagoras equation to obtain the value for
Conclusion:
Substitute
Substitute
By Flemings right hand rule, the thumb points towards the
The magnetic force vector on
(d)
The magnetic force vector on
Answer to Problem 20P
The magnetic force vector on
Explanation of Solution
Write the expression for the magnetic field in a wire,
Here,
Write the Pythagoras equation to obtain the value for
Conclusion:
Substitute
Substitute
By Flemings right hand rule, the thumb points the direction
The direction of the fore is
The magnetic force vector on
(e)
The force exerted on the forth segment from the forces on the other three.
Answer to Problem 20P
The force exerted on the forth segment from the forces on the other three can be determined by parallelogram law of vectors.
Explanation of Solution
Write the parallelogram law of vector equation.
Here,
Conclusion:
The force exerted on the forth segment from the forces on the other three can be determined by parallelogram law of vectors.
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Chapter 22 Solutions
Principles of Physics
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