You are asked to explain the earth's magnetic field. which is the best reply?

a.) the earth's magnetic south is similar to the north pole of a magnet.

b.) the earth's core has a strong magnetic charge similar to the south pole of a magnet.

c.) the earth's geomagnetic south is similar to the south pole of a magnet.

d.)the earth's magnetic charge is not centered at either pole; it varies based on location.

The free body diagram shows a box being pulled to the left up a 25-degree incline. the magnitude of the normal force is

When a vertical beam of light passes through a transparent medium, the rate at which its intensity i decreases is proportional to i(t), where t represents the thickness of the medium (in feet). in clear seawater, the intensity 3 feet below the surface is 25% of the initial intensity i0 of the incident beam. what is the intensity of the beam "10" feet below the surface? (give your answer in terms of i0. round any constants or coefficients to five decimal places.)

Acamcorder has a power rating of 20 watts. if the output voltage from its battery is 9 volts, what current does it use?