Answer:

Explanation:
Static friction occurs when an object initially starts at rest. When the surfaces of the materials touch, the microscopic unevenness interlock greatest with each other, causing the most friction out of the three.
During sliding friction, an object is already moving or in motion. The microscopic surfaces still interlock, but because the object is in motion, it has a momentum. Therefore, the magnitude of sliding friction is less than that of static friction.
Rolling friction occurs when an object rolls across some surface. Rather than surfaces interlocking, rolling friction is caused by the constant distortion of surfaces. As it rolls, the surfaces of the object are constantly wrapping and changing. This distortion causes the rolling friction. However, it is much less in magnitude when compared to static or sliding friction.
Answer:
alpha=53.56rad/s
a=5784rad/s^2
Explanation:
First of all, we have to compute the time in which point D has a velocity of v=23ft/s (v0=0ft/s)

Now, we can calculate the angular acceleration (w0=0rad/s)


with this value we can compute the angular velocity

and the tangential velocity of point B, and then the acceleration of point B:

hope this helps!!
We can conclude that it is a longitudinal wave because the wave is traveling through a medium displacing particles<span>
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Answer:
112.5 N
Explanation:
50 = GMm/r^2
Let F be the new force of attraction
F/50 = ( G(3M)(3m)/(2r)^2 ) / (GMm/r^2)
[Elimiating G,M,m,r]
F = 112.5 N