A rubber block weighing 60. Newtons is resting on a horizontal surface of dry asphalt. What is the magnitude of the minimum force needed to start the rubber block moving across the dry asphalt? 1. 32 n 2. 40. N 3. 51 n 4. 60. N.

Which of the following ideas did greek philosopher democritus contribute to the atomic theory? a. each object is made up of one atom, which varies in size from very small to very large. b. matter is composed of only one kind of particle, which can be easily destroyed. c. every element has a specific type of atom, which remains the same size in all forms of matter. d. all matter is composed of small particles, which combine to make larger objects.