Examine the Doppler effect illustration above. Assume the red dot is a police car with it's siren on. Which direction is the police car traveling?

-down
-left
-up
-right

What is the measurement of how fast an object moves relative to a reference point?

How much energy must a refrigerator absorb from 225 g of water so that the temperature of the water will drop from 35°c to 5°c

The electric potential v is constant everywhere within a certain region of space. which statement below is true? the choices are: the electric field is also constant (but not zero) within the region. a charged particle placed within the region will experience an electric force. the electric field is zero everywhere within the region. the electric field varies from place to place within the region.