<h2>MARK BRAINLIEST</h2>
For this assignment, you will develop several models that show how light waves and mechanical waves are reflected, absorbed, or transmitted through various materials. For each model, you will write a brief description of the interaction between the wave and the material. You will also compose two <u><em>typewritten</em></u> paragraphs. The first will compare and contrast light waves interacting with different materials. The second will explain why materials with certain properties are well suited for particular functions.
<h2><u>Background Information</u></h2>
A wave is any disturbance that carries energy from one place to another. There are two different types of waves: mechanical and electromagnetic. A mechanical wave carries energy through matter. Energy is transferred through vibrating particles of matter. Examples of mechanical waves include ocean waves, sound waves, and seismic waves. Like a mechanical wave, an electromagnetic wave can also carry energy through matter. However, unlike a mechanical wave, an electromagnetic wave does not need particles of matter to carry energy. Examples of electromagnetic waves include microwaves, visible light, X-rays, and radiation from the Sun.
Answer: V = 15 m/s
Explanation:
As stationary speed gun emits a microwave beam at 2.10*10^10Hz. It reflects off a car and returns 1030 Hz higher. The observed frequency the car will be experiencing will be addition of the two frequency. That is,
F = 2.1 × 10^10 + 1030 = 2.100000103×10^10Hz
Using doppler effect formula
F = C/ ( C - V) × f
Where
F = observed frequency
f = source frequency
C = speed of light = 3×10^8
V = speed of the car
Substitute all the parameters into the formula
2.100000103×10^10 = 3×10^8/(3×10^8 -V) × 2.1×10^10
2.100000103×10^10/2.1×10^10 = 3×108/(3×10^8 - V)
1.000000049 = 3×10^8/(3×10^8 - V)
Cross multiply
300000014.7 - 1.000000049V = 3×10^8
Collect the like terms
1.000000049V = 14.71429
Make V the subject of formula
V = 14.71429/1.000000049
V = 14.7 m/s
The speed of the car is 15 m/s approximately
The correct answer would be left
Work needed = 23,520 J
<h3>Further explanation</h3>
Given
height = 12 m
mass = 200 kg
Required
work needed by the crane
Solution
Work is the transfer of energy caused by the force acting on a moving object
Work is the product of force with the displacement of objects.
Can be formulated
W = F x d
W = Work, J, Nm
F = Force, N
d = distance, m
F = m x g
Input the value :
W = mgd
W = 200 kg x 9.8 m/s²x12 m
W = 23520 J