If 12 J of work are needed to stretch a spring from 8 cm to 12 cm and 20 J are needed to stretch it from 12 cm to 16 cm, what is the natural length of the spring?

Which of the following is not a characteristic of s waves? a. travel slower than p waves. b. cannot be detected in locations more than 105° from an earthquake’s epicenter. c. travel through solids and liquids. d. only affect coastal regions.

Suppose you have a box. which of these is not necessarily a true statement regarding the relationship between the force applied to the box, the work done on the box, and the distance the box is moved? a. if the box is not moved, no force is being applied to the box. b. if no force is applied to the box, no work is done on the box. c. if work is done on the box, then a force is applied to the box. d. if work is done on the box, then the box is moved a distance.

If the chemical properties of a substance remain unchanged and appearance or shape of a substance changes it is called a ?