Where is the point charge located and what is its charge in this electric field?

AI Thread Summary
The electric field measurements indicate a point charge is responsible for the varying magnitudes at two locations. The equations derived from the electric field values suggest that the charge is negative and located beyond x = 20 cm. However, calculations for the charge's location and magnitude have yielded incorrect results despite attempts to solve them. A critical note is made to measure distances in meters rather than centimeters for accurate calculations. Assistance is requested to resolve the discrepancies in the findings.
ajmCane22
Messages
33
Reaction score
0

Homework Statement



The electric field at the point x = 10.0 cm and y = 0 points in the positive x direction with a magnitude of 10.0 N/C. At the point x = 20.0 cm and y = 0 the electric field points in the positive x direction with a magnitude of 20.0 N/C. Assume that this electric field is produced by a single, point charge.

(a) Find the location of the point charge.

(b) Find the sign and magnitude of its charge.

The Attempt at a Solution



10 =q/4piε(d+10)^2

20 = q/4piε(d)^2
E is more at x=20 , so q must be -ve, and situated beyond x=20

dividing both eqn , we get
20/10 = d^2 + 100+ 20d/ d^2
solving the quadratic eqn , we get
d= 10±10√2
d= 24.14cm
put d= 24.14 in any above formula,

we get q= -0.13nC

Both answers are incorrect. I've gone to two different tutors and neither could help. Please help
 
Physics news on Phys.org
Measure distances in meters, not cm.
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Back
Top