Which of the following statements are true?a. Earth's geographic south pole is also a magnetic south pole. b. Scientists have evidence that single isolated magnetic poles, called magnetic monopoles, exist. c. The north pole of a bar magnet will attract the south pole of another bar magnet. d. The south poles of two bar magnets will repel each other. e. The north poles of two bar magnets will attract each other. f. Earth's geographic north pole is actually a magnetic south pole.

c, d, and f.

Explanation:

Let us look at each of the statements one at a time:

a. Earth's geographic south pole is also a magnetic south pole.

This is not true. Earths magnetic south pole is slightly off (2,860 km away) from earth's geographical south pole.

b. Scientists have evidence that single isolated magnetic poles, called magnetic monopoles, exist.

Nope. So far no evidence yet exists that hypothetical magnetic monopoles exist.

c. The north pole of a bar magnet will attract the south pole of another bar magnet.

True, since opposite ends of a magnet attract and like ends repel.

d. The south poles of two bar magnets will repel each other.

Also true since like poles of a magnetic repel each other.

e. The north poles of two bar magnets will attract each other.

No, the north poles of two magnets will repel each other since they have the same polarity.

f. Earth's geographic north pole is actually a magnetic south pole.

Yes. If you call the point of the needle that points north the north pole of the compass, then it points north because it is attracted to the south pole of earth's magnetic field. (like repel opposites attract)

answer: the potential energy decreases from 379 j to 243 j

explanation:

for the law of conservation of energy, the total energy in a system must be conserved. the total energy of the system is given by the sum of kinetic (k) and potential (u) energy:

e = k + u

the total energy is e=675 j, and this does not change.

initially, the kinetic energy is k=296 j, so the potential energy is

at the end, the kinetic energy is k=432 j, so the potential energy is

so, we see that the potential energy has decreased from 379 j to 243 j.