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3 years ago

Help with these please?

Physics

2 answers:

Anuta_ua [19.1K]3 years ago

5 0

E=kq/r^2

q=(E*r^2)/k

q=(.086N/C)(1.7m^2)/(8.99*10^9N*m^2/C^2)

q=2.76*10^-11 C

q=2.8*10^-11 C

Anettt [7]3 years ago

4 0

Another badly worded question. The Field is always directed away from the point charge. The question is the direction towards q or away from it and that's not much of an improvement.

Formula

E = k * q / r^2

Givens

k = 8.99 * 10^9 Nm^2/c^2

q = ??

E = 8.6*10^-2

r = 1.7 m

Solution

8.6*10^-2 * 1.7^2 / 8.99 * 10^9 = q

0.24 / 8.99 *10^9 = q

q = 2.8 * 10^-11

A but the wording is so bad that you have to guess what the question means. q is positive because the charge is going to the right away from the test charge.

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