Answer to Question #150709 in Electricity and Magnetism for jimmy

Question

A soccer goal, found in a city park, is made of tubing that supports an odd shaped hanging net behind the goal, but has a rectangular opening in front. The height of the opening is 2.5 m and the width is 3.2 m. If a uniform E-field, with a magnitude of 0.1 N/C, passes through the goal from the front to the back, entering at 90º to the plane of the goal opening, Calculate the flux through the net? Also, calculate the flux through the net if the E-field enters the goal at a 60° angle to the plane of the front of the goal. In both cases, assume that there is no charge found inside the goal itself. 

Answer 1

a)

$\Phi=EScos(90°-\alpha)=0.1\cdot 2.5\cdot 3.2\cdot0=0~V\cdot m,$

b)

$\Phi=EScos(90°-\beta)=0.1\cdot 2.5\cdot 3.2\cdot0.87=0.7~V\cdot m.$