The froghopper (philaenus spumarius), the champion leaper of the insect world, has a mass of 12.3mg and leaves the ground (in the most energetic jumps) at 4.00m/s from a vertical start. the jump itself lasts a mere 1.00ms before the insect is clear of the ground. (a) find the force that the ground exerts on the froghopper during its jump. (b) express the force of (a) in terms of the frog hoppers weight.

Four point charges each having charge q are located at the corners of a square having sides of length a. find symbolic expressions for the following. (a) the total electric potential at the center of the square due to the four charges (use any variable or symbol stated above along with the following as necessary: ke.) vtotal= (b) the work required to bring a fifth charge p from infinity to the center of the square (use any variable or symbol stated above along with the following as necessary: w=