A roller coaster car (shown below) has a mass of 1000 kg when fully loaded with passengers. Point A is 20 m below point 1 and point B is 25 m above A. Assuming that the way down is frictionless but not the way up, and the speed of the car at point 1 is 20 m/s, determine the following: B

There still seems to be an issue with this answer. The database is saying it's wrong.

5. The N pole faces of two cylindrical neodynium magnets having a radius of 0.5 cm and a length of 20 cm are brought together so that their faces are parallel and there is a small gap between them. The magnetic surface charge density on each pole face is 2 x 10° Cm's. (a) What is the force between the magnets in the limit in which the gap goes to zero? -Assume that the magnets are much longer than shown in the figure below, so that you only need to concern yourself with the repulsion between N and N. (b) What is the force between the magnets when they are separated by 0.5 m? At this separation you can approximate the four pole faces as point-charges.

One mole of carbon-12 has a mass of 12.00 grams. What is the mass of a 12C atom? Multiple Choice O 1.244 x 10-26 kg 2.032 × 10-26 kg 3.000 x 10-26 kg 2.440 x 10-26 kg 1.993 * 10-26 kg