A camera lens focuses on an object 78.0 cm from the lens. The
image forms 3.50 cm behind the
lens. If the object is 12.4 cm tall,
how tall is the image?
(Mind your minus signs.)
(Unit = cm)

Two charged particles, q1 and q2, are located on the x-axis, with q1 at the origin and q2 initially at x1 = 12.2 mm. in this configuration, q1 exerts a repulsive force of 2.62 µn on q2. particle q2 is then moved to x2 = 18.0 mm. what is the force (magnitude and direction) that q2 exerts on q1 at this new location? (give the magnitude in µn.)