Paul lifts a sack weighing 245 newtons vertically from the ground and places it on a platform at a height of 0.7 meters. if he takes 10 seconds to do this task, what power has he expended during this time?

Your science teacher brings in a speaker to talk to your class about climate change. during the session, students ask a few questions. which questions are related to the current evidence on climate change

Awelder using a tank of volume 7.50×10^-2 m^3 fills it with oxygen (with a molar mass of 32.0 g/mol ) at a gauge pressure of 3.30×10^5 pa and temperature of 37.1 ∘c. the tank has a small leak, and in time some of the oxygen leaks out. on a day when the temperature is 23.1 ∘c, the gauge pressure of the oxygen in the tank is 2.00×10^5 pa . a) find the initial mass of oxygen. b) find the mass of oxygen that has leaked out.

Which of the following is a transformer used for? alternate a voltage produce a voltage increase or decrease a voltage eliminate a voltage