Frequency is the number of occurrences of a repeating event per unit of time.It is also referred to as temporal frequency, which emphasizes the contrast to spatial frequency and angular frequency.
The period is the duration of time of one cycle in a repeating event, so the period is the reciprocal of the frequency.
Answer:
86.4 N downward
Explanation:
Force: This can be defined as the product of mass and acceleration of a body.
The S.I unit of Force is Newton(N).
The Expression of force is given as,
F = ma ................ Equation 1
Where F = force of the parachute harness, m = mass of the skydiver, a = acceleration of the skydiver.
Given: m = 72 kg, a = 1.2 m/s²
Substitute into equation 1
F = 72(1.2)
F = 86.4 N down ward.
Hence the force on the parachute harness = 86.4 N downward
Density is equal to mass divided by volume; that said, you would divide 38.6 by 2 to get your answer
William Parsons was the first astronomer to show that spiral nebulae have large Doppler shifts.
<h3>What are Spiral nebulae?</h3>
- In space, a nebula is a huge cloud of gas and dust. Some nebulae, including multiple nebulae, are made of gas and dust that have been released from the explosion of a dead star called a supernova. There are other nebulae that are star-forming regions.
- Edwin Hubble began observing Cepheid variables in many spiral nebulae, including the alleged Andromeda Nebula, in 1923, demonstrating that they are, in fact, full-fledged galaxies outside our own. Since then, the phrase spiral nebula has lost favor.
- One group of astronomers believed that spiral nebulae were parts of our Milky Way galaxy, whereas the other group believed that these objects were actual galaxies that were outside of the Milky Way galaxy.
To learn more about Nebulae visit:
brainly.com/question/6452529
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Σ/ε
σ = F/A
ε = ΔL/L
F = force
A = area
L = lenght
ΔL = |old lenght - new lenght|
