41. Electric and magnetic forces can both make certain objects move. For example, a positively charged particle will repel another positively charged particle. Which of these is the best way for a student to demonstrate the same principle using magnets?

Place the north pole of a magnet next to the north pole of another magnet.

Explanation:

Looking at the comments, we can see that the options are:

Place the south pole of a magnet next to the north pole of another magnet.

Place the north pole of a magnet next to the north pole of another magnet.

First, we know that a positively charged particle will repel another positively charged particle.

The same thing happens for magnetic forces (usually we define a magnetic flow from the south pole to the north pole, so we can define the south pole as the "positive" and the north pole as the "negative", but this is only notation and do not really matter), a south pole of a magnet will repel another south pole of a magnet (and the same happens for the north poles)

Then the correct option is:

Place the north pole of a magnet next to the north pole of another magnet.

answer: 802.3 kilo joules of energy represents 191.75 kilo calorie of energy.

explanation:

energy released during combustion of one mole methane = 802.3 kilo joules

if 1 kilo joule = 0.239006   kilo calorie

then ,802.3 kilo joule will be = 802.30.239006 kilo calorie

802.3 kilo joule = 191.75 kilo calorie

hence, the energy in kilo calorie is 191.75 kilo calorie.

i think they are all correct

explanation:

they seem good