Materials that allow the charges of an electric current to move freely through them are called

a. insulators.

b. conductors.

c. resistors.

d. magnets.

If you send a sound wave of the same wavelength (λ = 2.00 m) through air, helium, and carbon dioxide, describe how the pitch of the sound will compare through each medium.

if the resistance of a car headlight is 15 ohm and the current through it is 0.60, what is the voltage across the headlight?

The specific heat capacity of methane gas is 2.20 j/g-k. How many joules of heat are needed to raise the temperature of 5.00 g of methane from 36.0°c to 75.0°c?

What is an example of situational irony in the excerpt?

Ball A has mass 5.0 kg and is moving at - 3.2 m/s when it strikes stationary ball B, which has mass 3.9 kg, in a head-on collision. If the collision is completely inelastic, what is the common velocity of balls A and B?

As a fire truck approached Mary, the pitch of the siren got higher. once the fire truck passed and moved away, the sirens pitch got lower. this change in pitch is because in the sound waves

Find the magnitude of the sum of these two vectors

Light waves that cross from an air medium to a water medium will A. O be focused into a straight line. B. O lose energy and dissipate. C. O change length and direction. D. O reflect off the water's surface.

What is a possible cost of using nonrenewable energy resources? A. Costs more money B. Less water pollution C. Sustainable energy D. Greenhouse gases

Kara is writing a science-fiction story. In the story, Earth no longer experiences day and night. To return Earth to normal, which action should the heroine of the story take? A. She should get the Sun to travel around Earth again. B.