Asponge and a bar of soap occupy the same amount of space, but the soap is much more dense than the sponge

Describe the path of a ray that approaches a mirror parallel to the principal axis.

The current in a hair dryer measures 11 amps. the resistance of the hair dryer is 12 ohms. what is the voltage?unit:

Two objects of different mass start from rest, are pulled by the same magnitude net force, and are moved through the same distance. the work done on object 1 is 900 j. after the force has pulled each object, object 1 moves twice as fast as object 2. how much work is done on object 2?