The doppler effect is when waves’ wavelengths get squished when the source is moving toward you or stretched when the source is moving away from you. it can be observed with sound waves but not light waves because the speed of light is just too fast, meaning that we can’t move toward or away fast enough. (also some stuff with relativity).
Surface tension could be defined as the property of the surface of a liquid that allows it to resist an external force. The cohesive forces among liquid molecules are responsible for the phenomenon.
In simpler terms, it is the force that causes the molecules on the surface of a liquid to be pushed together and form a layer. The surface tension, then, is a measure of the cohesive forces that hold the molecules together.
Getting the actual measurement would give us 72 dynes/cm at 25°C . However, the force decreases significantly depending on the temperature.
Answer:
y = 428.67 m and x all = 1513.68 m
Explanation:
This problem of kinematics can be divided into two parts: a first part when the rockets work a second as a parabolic launch.
Let's do the first part, let's calculate the speed just when the engines turn off
vf = v₀ + at
vf = 78 + at
vf = 78 +12 3
vf = 114 m / s
This is the speed with which the second part begins vo = 114 m / s with an Angle of 38º
Also at this time a distance is displaced, we calculate the distance traveled (in the direction of the acceleration)
d = v₀ t + ½ a t²
d = 78 3 + ½ 12 3²
d = 288 m
Let's use trigonometry to find the components
x₀ = d cos 38 = 288 cos 38
y₀ = d sin38 = 288 sin38
x₀ = 226.95 m
y₀ = 177.31 m
Second part
Let's calculate the maximum height, at this point its vertical speed is zero (vfy = 0)
Let's decompose the initial velocity using trigonometry
vₓ = v₀ cos 38
= v₀ sin38
vₓ = 114 cos 38
= 114 sin38
vₓ = 89.83 m / s
= 70.19 m / s
² = ² - 2g (y -y₀)
0 = ² -2g (y -yo)
y-y₀ = ² / 2g
y-y₀ = 70.19²/2 9.8
y = 251.36 + y₀
y = 251.36 + 177.31
y = 428.67 m
This is the maximum height from the point where the movement began, that is, the ground.
Now let's calculate the range
R = vo² sin 2θ / g
R = 114² sin 2 38 /9.8
R = 1286.73 m
This is the scope of the parabolic movement, we must add the horizontal distance traveled in the first part
x all = R + xo
x all = 1286.73 + 226.95
x all = 1513.68 m
Answer:
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