Explain why if charge cannot be created or destroyed, electrically neutral objects can become electrically charged

If you run a complete loop around an outdoor track of length 400 m in 100 s, find your average velocity and average speed. Include units.

160 students sit in an auditorium listening to a physics lecture. Because they are thinking hard, each is using 125 W of metabolic power, slightly more than they would use at rest. An air conditioner with a COP of 5.

Determine the amount of time for polonium-210 to decay to one fourth its original quantity. The half-life of polonium-210 is 138 days. Explain.

What most likely caused geologists to accept Alfred Wegener's theory? A. After 50 years, the theory became popular. B. All hypotheses become theories after a long period of time. C. It took scientists a long time to understand Wegener's ideas. D.

What holds a moon in its orbit? A. the heat generated by the planet it orbits B. the gravitational pull of the star it orbits C. its own internal magnetism D. the gravitational pull of the planet it orbits

Protecting his nest, a 600-g peregrine falcon rams a marauding 1.5-kg raven in midair. the falcon is moving at 20.0 m/s, and the raven at 9.00 m/s at the moment of impact.

A carousel has a radius of 1.70 m and a moment of inertia of 110 kg · m2. A girl of mass 44.0 kg is standing at the edge of the carousel, which is rotating with an angular speed of 3.40 rad/s.

A 2kg marble is moving at 3 m/s when it strikes another 4kg marble moving in the opposite direction at - 3 m/s. What will be the velocity of the 4kg marble after the collision of the 2kg marble's new velocity is - 4 m/s.

How long did it take to reload a rifle during the 18th 19 century?

Hot spots in electronic and electric circuits can be detected visually with the use of A. dataloggers. B. thermocouples C. oscilloscopes D. infrared cameras.