# Electric field strength (should be easy)

1. Feb 2, 2005

What is the electric field strength in a region where the flux through a: $$1.0cm \times 1.0cm$$ flat surface is: $$65N\frac{m^2}{C}$$, if the field is uniform and the surface is at right angles to the field?

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Since the field points at a right angle to the surface we have a norm of 1. (cos(90) = 1).

So we have:

$$\phi = 65N\frac{m^2}{C}$$
$$A = (1.0cm)^2 = (0.01m)^2 = 0.0001m^2$$
$$E= unknown$$

Therefore:

$$\phi = E*A$$

$$65N\frac{m^2}{C}=E (0.0001)$$
$$E=\frac{65}{0.0001}\frac{Nm^2}{C}$$

Thus:
$$E=650000N\frac{m^2}{C}$$

Did I do this math correctly? I just feel like I am doing something wrong here. Thanks

2. Feb 2, 2005