CRAO is considered a stroke of the eye. Studies show that about two-thirds of patients have underlying high blood pressure and one-fourth of patients will have significant carotid artery disease (plaque with narrowing of the artery lining), cardiac valvular disease or diabetes.
Electrical pressure is measured in volts, or voltage. All electrical devices are rated for specific voltages. Most devices and small appliances in a home are rated for 120 volts, while high-voltage appliances, such as electric dryers, ranges, and many baseboard heaters, are rated for 240 volts.
Difference in Units. Energy is usually measured in Joules, the other units include ergs and calories. Power is measured in Watts, which is Joules per second, or ergs per second. Machine are usually described by its power rating, the higher the number the more powerful the machine.