Which of the following examples shows that a chemical reaction has occurred? O A solid is formed when heat is removed from a sample of water.
A rock breaks into smaller pieces when it is struck with a hammer.
O A cup of water turns pink when a few drops of red food coloring are added.
Bubbles form when baking soda is added to vinegar and mixed.

How does the image distance (di) of a convex lens compare with the image distance of a concave lens? a. the image distance of the convex lens is positive, and that of the concave lens is negative. b. both are negative for a virtual image. c. both are positive for a virtual image d. the image distance of the convex lens is negative, and that of the concave lens is positive.

Jackson is designing a new heater, and he wants to experiment with different thermally conductive materials. which of these materials would be useful in conducting heat?

Suppose an objects initial velocity is 10m/s and it’s final velocity is 4 m/s. mass is constant. what can best be concluded about the object based in the work-energy theorem