Soru
Suppose we are told that the acceleration a of a particle moving with uniform speed v in a circle of radius r is proportional to some power of r, say r^n , and some power of v, say v^m . Determine the values of n and m and write the simplest form of an equation for the acceleration. a=kr^nv^m
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Cevap
To determine the values of n and m, we need to consider the acceleration, radius, and velocity.<br /><br />The unit of acceleration is m/s², the unit of radius is m, and the unit of velocity is m/s.<br /><br />Let's analyze the equation $a=kr^{n}v^{m}$:<br /><br />1. The unit of $r^{n}$ is mⁿ, and the unit of $v^{m}$ is (m/s)ᵐ.<br />2. To make the equation dimensionally consistent, the units on both sides of the equation must be the same.<br /><br />Therefore, the unit of $kr^{n}v^{m}$ must be m/s².<br /><br />By equating the units, we get:<br /><br />mⁿ * (m/s)ᵐ = m/s²<br /><br />Simplifying the equation, we have:<br /><br />m = 2 - n<br /><br />Now, let's consider the physical meaning of the equation. The acceleration of a particle moving with uniform speed v in a circle of radius r is proportional to some power of r and some power of v. This means that as the radius or velocity increases, the acceleration also increases.<br /><br />From the equation $a=kr^{n}v^{m}$, we can see that as the radius (r) increases, the acceleration (a) increases if n is positive. Similarly, as the velocity (v) increases, the acceleration (a) increases if m is positive.<br /><br />Therefore, both n and m must be positive integers.<br /><br />From the unit analysis, we found that m = 2 - n. To satisfy the condition that both n and m are positive integers, we can set n = 1 and m = 1.<br /><br />Thus, the simplest form of the equation for the acceleration is:<br /><br />$a = kr^{1}v^{1}$<br /><br />or<br /><br />$a = kv$<br /><br />where k is a constant of proportionality.
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