What is the role of the communicator in a dc generator? A) it keeps the electric current flowing in one direction
B) it keeps the magnetic fields of the permanent magnet steady
C) it causes the magnetic fields of the permanent magnets to reverse
D) it causes the electric current to constantly reverse its direction

6–48 bananas are to be cooled from 24 to 138c at a rate of 215 kg/h by a refrigeration system. the power input to the refrigerator is 1.4 kw. determine the rate of cooling, in kj/ min, and the cop of the refrigerator. the specific heat of banana above freezing is 3.35 kj/kg·8c.

Properties seen when one one substance changes to another are known as properties

Blood pressure the total amount of blood the heart pumps in one minute 2. cardiac output the number of times your heart beats in a minute 3. dilate the amount of blood that the heart can pump in a single beat 4. heart rate the force exerted on the walls of the blood vessels by the blood that moves through them 5. stroke volume to widen or get larger in size