I painted the inner four walls of a box. Then I put an ice block into it such that it did not touch the walls, but I couldn't do the same when I put water in that box. Why?

When considering gravity acceleration and the force of acceleration, what must be true? a. the direction of acceleration must be perpendicular to the direction of the force. b. the direction of the force and the direction of acceleration must be the same as each other. c. the direction of the force and the direction of acceleration must be opposite of each other. d. the mass of the body must be the same as the acceleration of the body.

What are similarities and differences of reflection, refraction, diffraction and absorption?

The coefficient of friction is a number that represents the resistance to sliding between two in contact with one another.