Calculate the electrical energy expended in a device across which the circuit voltage drops by 40.0 volts in moving a charge of 2 coulombs.

A) 20

B) 80

Usable energy is lost each time energy is converted to another form of energy. true or false

Which two statements are true about a system? A system is a group of objects analyzed as one unit. Energy that moves across system boundaries is conserved. There's only one way to define the boundaries of a system. All systems are made by humans.

In lab you find that a 1-kg rock suspended above water weighs 10 N. When the rock is suspended beneath the surface of the water, the scale reads 8 N. a. What is the buoyant force on the rock? b.

A 3.8 kg object is lifted 12 meters. approximately how much work is performed during the lifting?

A 38-kilogram canoe broke free of its dock and is now floating downriver at a speed of 2.2 m/s? Show your work.

Explain why cool rock material sinks when convection takes place in the mantle?

Both artists and scientists contribute to our understanding of the world around us. Identify the ways that art and science are similar. Check all that apply.

An automobile accelerates from rest at 1 + 3 * sqrt (t) mph/sec for 9 seconds. how far does it travel in those 9 sec?

A glass lens, n glass = 1.52, has a 131 nm thick antireflective film coating one side, n film = 1.25. White light, moving through the air, is perpendicularly incident on the coated side of the lens.

An automobile steering wheel is shown. The ideal mechanical advantage of this wheel and axle is. If a driver must exert a force of 2 N to overcome an axle resistance of 16 N, the AMA of the steering wheel is and its efficiency is__ %.?