A roller waster with a mass of 900kg coasting on a track. When it reaches points A, it is moving at 5m/s. Assume there is no friction and air resistance. Calculate the velocity of the roller at point B. ​

Sawyer is studying diffraction. he draws a diagram of a plane wave to show how light waves travel. which best describes sawyer’s error? the wave fronts should be perpendicular to the direction in which the waves move. the arrow showing the direction of movement of the waves should be pointing to the left. the arrow showing the direction of movement of the waves should be pointing downward. the wave fronts should be both parallel and perpendicular to the direction in which the waves move.

Chemical energy is a form of energy. a. heat b. kinetic c. potential d. electromagnetic

You've already seen the value of 9.8 in this lesson. what's this value called? what quantity does it represent?