At which position a or b is the potential energy of the swing the greatest

1. jay fills a wagon with sand (about 20 kg) and pulls it with a rope 30 m along the beach. he holds the rope 25° above the horizontal. the rope exerts a 20-n tension force on the wagon. how much work does the rope do on the wagon?

Match these items. 1. coulombs __force 2. ohms __emf 3. centimeters __resistance 4. newtons __charge 5. volts __length

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?