2 years ago

Why do scientists believe the universe is still expanding?

1 answer:

5 0

I don’t understand the question

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JulijaS [17]

It refers to a base substitution<span> when the change in nucleotide changes the amino acid coded for by the </span>affected<span> codon</span>

6 0

3 years ago

Gemiola [76]

Answer:

α = 200*π rad/sec²

Explanation:

If the disk drive revolves once every 0.05 sec, this means that the angular velocity can be expressed as follows:

$\omega = \frac{2*\pi}{0.05s} = 40*\pi rad/sec$

(just applying the definition of angular velocity)
Now, it the disk started from rest, and took two revolutions to reach to full speed, assuming that the angular acceleration is constant, we can find the angular acceleration applying this kinematic equation:

$\omega_{f} ^{2} -\omega_{0} ^{2} = 2*\alpha * \Delta\theta$

where Δθ, is the angle rotated while it went from rest to full speed, i.e., 2 revolutions, or 2*π rads.
Replacing by the value that we found for ωf (as ω₀ = 0), we can solve for α :

$\alpha =\frac{\omega_{f}^{2} }{2*\Delta\theta} = \frac{(40*\pi)^{2} }{2*2*2*\pi } =\\ \\ \alpha = 200*\pi rad/sec2$