Problem 14.19 Bees acquire an electric charge in flight from friction with the a
ID: 1410214 • Letter: P
Question
Problem 14.19 Bees acquire an electric charge in flight from friction with the air, which causes pollen to cling to them. The pollen is then attracted to the stigma of the next flower as shown in the figure (Figure 1) . Suppose the bee's body has a charge of 1.0×10^-9C and is about 3.2 ×10^-3m from the front edge of a spherical granule of pollen of diameter 4.6 ×10^-5 m. Charged particles in the pollen become polarized with +10^-11C on the front edge and 10^-11C on the backside of the pollen (3.2 ×10^-3 + 4.6 ×10^-5) m from the bee.
Part A Determine the force exerted on the bee by the polarized charge distribution on the pollens. For the positive direction of the force take direction from the bee to pollen. Express your answer to two significant figures and include the appropriate units.
Fqonbee =
Part B Determine the electric potential energy of the bee-pollen system. Express your answer to two significant figures and include the appropriate units.
Uq =
Explanation / Answer
PART A)
F = sigma kqQ/r^2
= 9*10^9*[1.0×10^-9]*[10^-11/(3.2 ×10^-3)^2 - 10^-11/(3.2 ×10^-3 + 4.6 ×10^-5)^2]
= 2.473 *10^-7 N
PRT B)
U = k[q1q2/r12 +q3q2/r23+q1q3/r13]
=9*10^9*[-1.0×10^-9*10^-11/(3.2 ×10^-3) - 1.0×10^-9*-10^-11/(3.2 ×10^-3 + 4.6 ×10^-5) + 10^-11*-10^-11/(4.6 ×10^-5)
= - 2.0 *10^-8 J