At constant temperature and pressure, is work done by the system on the surroundings? by the surroundings onto the system? or is no work done? i2(s) ������ i2(g).

An object is 10. cm from the mirror, its height is 3.0 cm, and the focal length is 2.0 cm. what is the image height? (indicate the object orientation by including the + or - sign with the answer.) hi = cm +1.33 -1.33 +0.75 -0.75

I'm thinking it's 2 you are asked to explain the earth's magnetic field. which is the best reply? 1. the earth's magnetic south is similar to the north pole of a magnet. 2. the earth's core has a strong magnetic charge similar to the south pole of a magnet. 3. the earth's geomagnetic south is similar to the south pole of a magnet. 4. the earth's magnetic charge is not centered at either pole; it varies based on location.

Two balls, each with a mass of 0.5 kg, collide on a pool table. is the law of conservation of momentum satisfied in the collision? explain why or why not