The stopping sight distance for a car traveling at 50 mph is 461 ft (including both perception-reaction distance and braking distance). The perception-reaction time is 2.5 sec. If a car traveling at 60 mph is to stop in the same distance with the same deceleration, what is most nearly the required perception-reaction time

Scout feels ill one day before school. her mother puts a thermometer in her mouth and the temperature begins to climb to 100°f. what is happening between the cooler thermometer and scout's body? a) scout's body is applying a force to the particles in the thermometer. b) kinetic energy is being transferred from her mouth to the thermometer. c) potential energy is being lost by the thermometer and gained by scout's body. d) the potential energy stored in foods is converted to mechanical energy to raise the mercury in the thermometer.

Acompound machine is also called a machine. a. force b. simple c. complex d. directional

Debris produced by mining is called