Answer:
The mass of the sand that will fall on the disk to decrease the is 0.3375 kg
Explanation:
Moment before = Moment after

where;
I is moment of inertia = Mr² = 0.3 x (0.3)² = 0.027 kg.m²
substitute this in the above equation;
![m = \frac{ 0.027[3(2 \pi) - 2(2 \pi)]} {0.2^2 * 6\pi } = \frac{ 0.027[6 \pi - 4\pi]} {0.2^2 * 4\pi }\\\\m = 0.3375kg](https://tex.z-dn.net/?f=m%20%3D%20%5Cfrac%7B%200.027%5B3%282%20%5Cpi%29%20%20-%202%282%20%5Cpi%29%5D%7D%20%7B0.2%5E2%20%2A%206%5Cpi%20%7D%20%3D%20%5Cfrac%7B%200.027%5B6%20%5Cpi%20%20-%204%5Cpi%5D%7D%20%7B0.2%5E2%20%2A%204%5Cpi%20%7D%5C%5C%5C%5Cm%20%3D%200.3375kg)
Therefore, the mass of the sand that will fall on the disk to decrease the is 0.3375 kg
Answer:
(c) 16 m/s²
Explanation:
The position is
.
The velocity is the first time-derivative of <em>r(t).</em>
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The acceleration is the first time-derivative of the velocity.

Since <em>a(t)</em> does not have the variable <em>t</em>, it is constant. Hence, at any time,

Its magnitude is 16 m/s².
21. light changes its direction when travelling through a new medium because denser mediums have a higher angle of refraction.
Answer:
The smallest separation distance between the speakers is 0.71 m.
Explanation:
Given that,
Two speakers, one directly behind the other, are each generating a 240-Hz sound wave, f = 240 Hz
Let the speed of sound is 343 m/s in air. The speed of sound is given by the formula as :

To produce destructive interference at a listener standing in front of them,

So, the smallest separation distance between the speakers is 0.71 m. Hence, this is the required solution.
The time elapsed since you stopped the stopwatch is 0.41 s.
<em>Your question is not complete, it seems to be missing the following information;</em>
"The velocity of the ant is 2 m/s"
The given parameters;
- velocity of the ant, v = 2 m/s
- change in position of the ant, Δx = 0.81 m
- time when the ant was noticed, = t₂
Velocity is defined as the change in displacement per change in time of motion of an object.

The time elapsed since you stopped the stopwatch is calculated as;

Thus, the time elapsed since you stopped the stopwatch is 0.41 s.
Learn more here: brainly.com/question/18153640