Helioseismology in an Alternate Universe 0 points possible (ungraded) Stars, like planets, can vibrate. On Earth, we call these vibrations earthquakes, and their study is called seismology. The study of the vibrations of the sun is called helioseismology. Earth's crust is made up of solid, rigid rock, so elastic forces are largely responsible for the propagation of earthquake vibrations. Stars, however, are made of hot plasma, so elastic forces are negligible. Instead, the relevant force in an oscillating star is gravity. In our universe, the force of gravity between two objects is F, (r) = Gm1m₂ where G is the Newton's gravitational constant, m₁ and m₂ are the masses of the two objects, and is the distance between the objects. Imagine that we are in an alternate universe in which the force of gravity is instead given by Fg (r) = Zm1m₂ Mass, distance, and force all have the same units in this alternate universe, i.e. kilograms, meters, and Newtons (kg-m/s²), respectively, and Z is Notwen's gravitational constant, which is analogous to G. (Part a) What are the dimensions of Z? Express your answer in terms of some or all of the following: M for mass, I for length, and T for time. (Part b) Since the stellar oscillations are governed by the gravitational force, the frequency of a star's oscillations will depend the gravitational constant Z and the star's density, p, and radius, R, i.e. w=w (p, R, Z). Using dimensional analysis, find a combination of p, R, and Z that has the units of frequency, i.e. s-¹. Your answer may contain some or all of the following: p, R, and Z. Note that you could do the exact same analysis to find the frequency of oscillations of a star in our universe, and the answer that you'd get would actually be quite accurate!
Simple harmonic motion
Simple harmonic motion is a type of periodic motion in which an object undergoes oscillatory motion. The restoring force exerted by the object exhibiting SHM is proportional to the displacement from the equilibrium position. The force is directed towards the mean position. We see many examples of SHM around us, common ones are the motion of a pendulum, spring and vibration of strings in musical instruments, and so on.
Simple Pendulum
A simple pendulum comprises a heavy mass (called bob) attached to one end of the weightless and flexible string.
Oscillation
In Physics, oscillation means a repetitive motion that happens in a variation with respect to time. There is usually a central value, where the object would be at rest. Additionally, there are two or more positions between which the repetitive motion takes place. In mathematics, oscillations can also be described as vibrations. The most common examples of oscillation that is seen in daily lives include the alternating current (AC) or the motion of a moving pendulum.
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