Question

In: Physics

A line of charge is placed on the x-axis between x = -5 m and x...

A line of charge is placed on the x-axis between x = -5 m and x = 5 m . The linear charge density is -10 microcoulomb per cm . Consider a field point on the y-axis, located at y - 2.0 m.

a. (2 points) How much charge dq is contained in a segment of the wire of length dx?

b. (5 points) Charge element dq is located at the point (x, 0). What is the distance r from the charge element to the field point? (Hint: Your answer should be a function of x.)

c. (5 points) What is the unit vector r hat associated with the electric field for this charge element dq? (Hint: Your answer should be a function of x and the unit vectors i hat and j hat)

d. (5 points) If there is symmetry to the problem, what is the only component of r hat needed (is not zero after integration)? If there is no symmetry that can be exploited, say “no symmetry”.

e. (20 points) What is the electric field vector at the field point? (Use the Cartesian unit vectors in your answer for E; do not simply say “up”, “left”, etc.)

f. (10 points) Suppose you placed a +10 microcoulomb charge at the field point. Would it be attracted toward the x-axis, pushed away from the x-axis, or neither? What is the magnitude of the force acting upon it?

Solutions

Expert Solution

(a) How much charge dq is contained in a segment of the wire of length dx?

. The linear charge density is -10 microcoulomb per cm, then we can write it as:

(b) Charge element dq is located at the point (x, 0). What is the distance r from the charge element to the field point? (Hint: Your answer should be a function of x.)

As the field point is located at y: - 2 m, then we can write the expression for r as:

(c) What is the unit vector r hat associated with the electric field for this charge element dq? (Hint: Your answer should be a function of x and the unit vectors i hat and j hat)

The unit vector can be written as:

(d)  If there is symmetry to the problem, what is the only component of r hat needed (is not zero after integration)? If there is no symmetry that can be exploited, say “no symmetry”.

As there is symmetry with respect to he Y axis, the y component is the one necessary:


Related Solutions

Two charges are placed along the x axis such that charge A is at -3 m,...
Two charges are placed along the x axis such that charge A is at -3 m, and has a charge of 2.5e-06 C. Charge B is at 2.2 m, and has a charge of -2.5e-06 C. What is the x component of the force (in Newtons) felt by charge A due to charge B? What is the x component of the force (in Newtons) felt by charge B due to charge A? Suppose a third charge were to be placed...
Positive charge A of charge 0.1 mC is placed at the origin of axis x, charge...
Positive charge A of charge 0.1 mC is placed at the origin of axis x, charge B, also positive, but of magnitude 4 times greater than A is placed at x=24.3 cm. These charges if released will run away from each other, but they are kept in place by the third charge positioned somewhere on the axis x. Find the value of this third charge (in mC).
Three point charges are placed on the x-axis. A charge of +2.0 μC is placed at...
Three point charges are placed on the x-axis. A charge of +2.0 μC is placed at the origin, -2.0 μC to the right at x = 50 cm, and +4.0 μC at the 100 cm mark. What are the magnitude and direction of the electrostatic force which acts on the charge at the origin?
(a)Two charges are placed on the x-axis: one is placed at x = 3 m and...
(a)Two charges are placed on the x-axis: one is placed at x = 3 m and the other is at x = -3 m. The magnitude of both charges is 9.7
4. A +15 nC point charge is placed on the x axis at x = 1.5...
4. A +15 nC point charge is placed on the x axis at x = 1.5 m, and a -20 nC charge is placed on the y axis at y = -2.0m. What is the magnitude of the electric field at the origin? a) 33.6 N/C b) 64.8 N/C c) 54.4 N/C d) 91.6 N/C e) 74.9 N/C
A +2.00 nC point charge and -3.00 nC point charge are placed along the x-axis at  x...
A +2.00 nC point charge and -3.00 nC point charge are placed along the x-axis at  x = 1.0 m and x = 2.0 m, respectively. Where must a third charge, q, be placed along the x-axis so that it does not experience any net electric force due to the other two charges
A point particle with charge q = 4.2 ?C is placed on the x axis at...
A point particle with charge q = 4.2 ?C is placed on the x axis at x = ?10 cm and a second particle of charge Q = 7.8 ?C is placed on the x axis at x = +25 cm. (a) Determine the x and y components of the electric field due to this arrangement of charges at the point (x, y) = (10, 10) (the units here are centimeters). Ex =  N/C Ey =  N/C (b) Determine the magnitude and...
Charges are placed on the x-axis as follows: q1 = + 5 μC at x =...
Charges are placed on the x-axis as follows: q1 = + 5 μC at x = -5 m q2 = − 3 μC at x = -1 m q3 = − 2 μ C at x = +2 m q4 = + 9 μ C at x = +3 m What is the net force on q2? Answer in units of milli-Newtons rounded to 3 significant figures.
Two point charges are placed on the x axis as follows: Charge q1 = 4.00nC is...
Two point charges are placed on the x axis as follows: Charge q1 = 4.00nC is located at x = 0.200m , and charge q2 = 5.00nC is at x=?0.300m. What are the magnitude and direction of the net force exerted by these two charges on a negative point charge q3 = -0.600nC placed at the origin? A. magnitude B. direction
1.2.1. A positive point charge ? is placed on the −?-axis at ? = −?, and...
1.2.1. A positive point charge ? is placed on the −?-axis at ? = −?, and a negative point charge −? is placed on the +?-axis at ? = ?. A positive point charge ? is located at some point on the +?-axis. (a) In a free-body diagram, show the forces that act on the charge ?. (b) Find the ?- and ?-components of the net force that the two charges ? and −? exert on ?. (Your answer should...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT