What is the net force?(please don't forget the direction and magnitude)

Which configuration would produce an electric current? a) rotate a coil of copper wire between two magnets. b) connect a wire between a copper and zinc strip sitting in a beaker of water. c) connect a wire to the (+) positive end of a battery and the other end to a light bulb. d) connect a wire to the negative end of a battery and the other end to a light bulb.

Awave that is traveling fast can be said to have a high a. frequency b. speed c. wavelength d. amplitude e. period f. none of these

The doctor lands his tardis on a planet whose radius is 1.2x10^7m the acceleration due to gravity is 18m/s^2. what is the mass of the planet