Electromagnetic waves are classified into forms such as radio waves, microwaves, and infrared waves, based on the amount of energy they carry. which property of an electromagnetic wave determines the level or amount of energy it carries?
a) speed
b) intensity
c) phase
d) wavelength

D) wavelength

Explanation:

The energy of an electromagnetc wave is given by the following formula:  

(1)

Where:  

is the Planck constant  

is the frequency  

Now, the frequency has an inverse relation with the wavelength :  

(2)  

Where is the speed of light in vacuum

Substituting (2) in (1) we have:

(3)

This means the amount of energy an electromagnetic wave carries depends on its wavelength (or its frequency), because the speed of light and are constant.

The property is D) wavelength.

Wavelength can be found by the distance between successive points on a wave. It can be consecutive corresponding crests, troughs or zero crossings. We can get the most accurate form of wavelength on sinusoidal waves, which are smooth and repetitive.

Two waves which are travelling with the same rate of speed can have different wavelength with varied frequencies. A light’s wavelength varies with varying color.

For example: the wavelength of red is longer than violet.

what experimental evidence led scientists to change from the previous model to this one?

a few of the positive particles aimed at a gold foil seemed to bounce back.

the colors of light emitted from heated atoms had very specific energies.

experiments with water vapor showed that elements combine in specific proportions.

cathode rays were bent in the same way whenever a magnet was brought near them.

the old price per ounce is c/4.

the new price per ounce is c/3.6.

the ratio of the old price to the new one is

(c/4)/(c/3.6) = (c/c)×(3.6/4) = 0.9 . . = 9/10 . . "nine tenths" in either form