Which of the following is a trend among the main sequence stars?

A) Most of the stars are white or red.

B)The hotter the star, the more brightly it burns.

C) Stars dimmer than the Sun are of class O or B

D) The larger stars emit light that is blue.

Two particles of masses m and 2m are placed on a smooth horizontal table. a string, which joins these two masses, hangs over the edge supporting a pulley, which suspends a particle of mass 3m.the pulley has negligible mass. the two parts of the string on the table are parallel and perpendicular to the edge of the table. the hanging parts of the string are vertical. find the acceleration of the particle of mass 3m.

Which is an example of an exothermic process?

Which planet do you think would be easiest for humans to colonize some day?