I think it is kinetic friction not the best at physics
Answer:
M = 175 kg
Explanation:
In the resolution of the harmonic oscillator movement of a system and a mass with a spring, the angular velocity is
w = √ k / m
Where k is the spring constant and m the mass
In this case the mass is the mass of the chair (m) plus the mass of the astronaut (M)
M all = m + M
The angular velocity and the period are related by
w = 2π / T
Substituting
2π / T = √(k/(m + M))
We calculate the astronaut's mass
4π² / T² = k / (m + M)
M = k T² / 4π² - m
M = 569 3.6² /(4π²) - 11
M = 186.8 - 11
M = 175 kg
The lightbulb, the fire, and the Sun all create light from some energy source.
The Moon doesn't create light. The parts of it that the Sun shines on
are visible, the parts of it that the Sun doesn't shine on are not visible.
Just like a rock on the ground at night, the Moon must be illuminated
by a flashlight in order to be seen. The Sun is the flashlight.
A. Light travels in a straight line.
<u>Expliantion: study island</u>
