Manipulate the distance between the object and the lens ([math]d_o[/math]) and see how the distance between the image and the lens ([math]d_i[/math]).[br][br]Record [math]d_o[/math] and [math]d_i[/math], for at least 5 different lengths.[br][br]Graph [math]\frac{1}{d_o}[/math] vs [math]\frac{1}{d_i}[/math] to determine the focal length of the lens.