Both slicing a tomato and burning toast cannot be reversed, so why is slicing a tomato only considered a physical change?

Aparticle initially moving east with a speed of 20.0 m/s, experiences an acceleration of 3.95 m/s, north for a time of 8.00 s. what was the speed of the particle after this acceleration, in units of m/s? give the answer as a positive number.

At very high pressures, gases become and will eventually a) more dense; become hotter b) more dense; change to a liquid or solid c) less dense; combust d) less dense; turn into a liquid

One form of energy can be another type of energy. a. created to form b. transformed into c. destroyed and then created to form