Which is an indication that a chemical change to a substance has occurred?

A.

It changes shape.

B.

New substances are formed.

C.

Energy is used or given off.

D.

both B and C

A wire has a current that flows to the right. Which describes the magnetic field produced by the current?

What are the significant of determination of light

A swimming duck paddles the water with its feet once per time interval of 1.6 s, producing surface waves with this period. The duck is moving at constant speed in a pond where the speed of surface waves is 0.

What do volcanoes look like inside?

A cosmic-ray proton in interstellar space has an energy of 59 MeV and executes a circular orbit with a radius equal to that of Mercury's orbit (5.8 * 1010 m) around the Sun.

Two sinusoidal waves are moving through a medium in the positive x-direction, both having amplitudes of 7.00 cm, a wave number of k=3.00m-1, an angular frequency of ω=2.50s-1, and a period of 6.00 s, but one has a phase shift of an angle ϕ=π12rad.

For a vacation, you and your family fly east to west from Boston, Massachusetts, to Seattle, Washington. You notice that your flight back home to Boston is shorter than your flight to Seattle. Which phenomenon causes your flight home to be shorter?

You spy on an anchor on the bottom of a lake. What is the direction and amount of force the water exerts on it: a) zero b) up, equal to the weight of the anchor. c) up, less than the weight of the anchor d) down, equal to the weight of the anchor.

How are electromagnetic waves different from matter waves?

A dc generator is the same as a (n) a. electric motor. b. ac generator. c. armature. d. electric current.