a book with a mass of 1.8 kg sits on a bookshelf. if it has a gravitational potential energy of 42 J, how high is the Shelf? The acceleration of the gravity is 9.8 m/s^2. A) 2.1 B) 2.4 C) 1.6 D) 0.9

You have been called to testify as an expert witness in a trial involving a head-on collision. car a weighs 1515 lb and was traveling eastward. car b weighs 1125 lb and was traveling westward at 44.0 mph. the cars locked bumpers and slid eastward with their wheels locked for 22.5 ft before stopping. you have measured the coefficient of kinetic friction between the tires and the pavement to be 0.750 . how fast (in miles per hour) was car a traveling just before the collision? (this problem uses english units because they would be used in a u. s. legal proceeding.)

What is the difference between electrically neutral objects and electrically charged objects

Which lists the pairs of plates in order from least to greatest in terms of the work done to move the electron?