What is the conservation of energy?

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.

Heena wants to measure the volume of a ball that is 24 cm across. how should she set up her equation?

Which features on mars point to the possibility of liquid water on the planet? impact craters with sharp rims volcanic cones with craters gullies and stream-like channels mountain ranges with faults