The electric force due to a uniform external electric field causes a torque of magnitude 16.0 ×× 10−9−9 N⋅mN⋅m on an electric dipole oriented at 30∘∘ from the direction of the external field. The dipole moment of the dipole is 8.5 ×× 10−12−12 C⋅mC⋅m. What is the magnitude of the external electric field? If the two particles that make up the dipole are 2.5 mm apart, what is the magnitude of the charge on each particle?

Afisherman notices that his boat is moving up and down periodically without any horizontal motion, owing to waves on the surface of the water. it takes a time of 2.20 s for the boat to travel from its highest point to its lowest, a total distance of 0.670 m . the fisherman sees that the wave crests are spaced a horizontal distance of 5.80 m apart. (a) how much is the wavelength? (b) find the period of the wave. (c) how fast are the waves traveling? (d) what is the amplitude a of each wave?