1. a. longitudinal waves.
There are two types of waves:
- Transverse waves: in transverse waves, the oscillations of the wave occur in a direction perpendicular to the direction of propagation of the wave
- Longitudinal waves: in longitudinal waves, the oscillations of the waves occur parallel to the direction in which the waves are travelling.
So, these types of waves are called longitudinal waves.
2. d. a medium
There are two types of waves:
- Electromagnetic waves: these waves are produced by the oscillations of electric and magnetic field, and they can travel both in a medium and also in a vacuum (they do not need a medium to propagate)
- Mechanical waves: these waves are produced by the oscillations of the particles in a medium, so they need a medium to propagate - therefore, the correct choice is d. a medium
3. a. AM/FM radio
Analogue signals consist of continuous signals, which vary in a continuous range of values. On the contrary, digital signals consist of discrete signals, which can assume only some discrete values. For AM and FM radios, signals are transmitted by using analogue signals.
<em>Answer: </em>tellurium (Te)
<em>atomic number = 52 ,</em>
<em>Number of energy levels = 5;</em>
First energy level = 2
Second energy level = 8
Third energy level = 18
Fourth energy level = 18
Fifth energy level = 6
<em>In this electron configuration, 0uter most electrons are 6.</em>
Answer:
0.050 m
Explanation:
The strength of the magnetic field produced by a current-carrying wire is given by

where
is the vacuum permeability
I is the current in the wire
r is the distance from the wire
And the magnetic field around the wire forms concentric circles, and it is tangential to the circles.
In this problem, we have:
(current in the wire)
(strength of magnetic field)
Solving for r, we find the distance from the wire:

Answer:
to overcome the out of friction we must increase the angle of the plane
Explanation:
To answer this exercise, let's propose the solution of the problem, write Newton's second law. We define a coordinate system where the x axis is parallel to the plane and the other axis is perpendicular to the plane.
X axis
fr - Wₓ = m a (1)
Y axis
N-
= 0
N = W_{y}
let's use trigonometry to find the components of the weight
sin θ = Wₓ / W
cos θ = W_{y} / W
Wₓ = W sin θ
W_{y} = W cos θ
the friction force has the formula
fr = μ N
fr = μ Wy
fr = μ mg cos θ
from equation 1
at the point where the force equals the maximum friction force
in this case the block is still still so a = 0
F = fr
F = (μ mg) cos θ
We can see that the quantities in parentheses with constants, so as the angle increases, the applied force must be less.
This is the force that balances the friction force, any force slightly greater than F initiates the movement.
Consequently, to overcome the out of friction we must increase the angle of the plane
the correct answer is to increase the angle of the plane
Rosalind Franklin, James Watson, and Francis Crick’s discovered the DNA's Double Helix.
<h3>What is DNA?</h3>
DNA is an abbreviation for deoxyribonucleic acid and it can be defined as the molecules that are found within cells, and they are saddled with the responsibility of storing genetic information in living organisms.
In 1953, James Watson and Francis Crick's used other scientists' work to create a model of DNA in that they used Rosalind Franklin's photo to help them determine that deoxyribonucleic acid (DNA) was a double helix.
Furthermore, the discovery of DNA's Double Helix by Rosalind Franklin, James Watson, and Francis Crick led to modern molecular biology, which has helped many scientists and researcher to understand how genes control the chemical processes in the body of a living organism.
Read more on DNA's Double Helix here: brainly.com/question/26733817
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