Sonia was experimenting with electric charges. She tied two inflated balloons together, held them next to each other, and rubbed both with a piece of wool. What did Sonia observe, and why?

Two bricks of the same mass are each on ledges. Brick 1 is 100 feet high and Brick 2 is 300 feet high. Brick 2 has: 1. zero times more potential energy 2. two times more potential energy 3. three times more potential energy 4.

The principal reason voltage is induced in the loops of a generator coil is that the a. loops are rotating, changing the amount of magnetic field within the loops. b. size of the loops is changing. c. magnet's strength is changing. d.

List two examples of ways to increase efficiency in a machine.

About 30 % of earth's water found In

The nucleus consists of two types of particles, called protons and neutrons. A. True B. False

Combining which of the following substances with germanium will cause the germanium to emit free electrons? A. Bismuth B. Gallium C. Aluminum D. Indium

A 50.0-g Super Ball traveling at 25.0 m/s bounces off a brick wall and rebounds at 22.0 m/s. A high-speed camera records this event. If the ball is in contact with the wall for 3.

A heat engine with a thermal efficiency of 45 percent rejects 500 kj/kg of heat. how much heat does it receive

Which was least likely to have been a component of Earth's atmosphere before life began? A-sulfur B-carbon dioxide C-oxygen D-water vapor

Vector A makes equal angles with x, y and z axis. value of its components (in terms of magnitude of vector A will be?