Which would best help a student determine the net force acting on a rollercoaster car as it moves from one point on its track to another?

The field between two charged parallel plates is kept constant. if the two plates are brought closer together, the potential difference between the two plates either a) decrease b) does not change c) increase?

Water is siphoned from a large tank and discharges into the atmosphere through a 50-mm diameter tube. the end of the tube is b = 2.6 m below the tank bottom which is a = 6.7 m deep, and viscous effects are negligible. determine the maximum height h over which the water can be siphoned without cavitation occurring. atmospheric pressure is 101.4 kpa, and the water vapor pressure is 1.79 kpa (absolute). report your answer in meters to two decimal places.

Another word for electromagnetic energy is a. heat b. force c. matter d. radiation