Answer:
400 N
Explanation:
Change of Kinetic Energy to Friction Wok
∆KE = W
½ x m x (v(5)² - v(3)²) = f x d
½ x 500 x (5² - 3²) = f x 10
250 x (25 - 9) = f x 10
25 x 16 = f
f = 400 N
Answer:
0.453 m/s
Explanation:
Assuming the handle has diameter of 0.4 m while inner part diameter is 0.1 m then the circumference of outer part is 
where d is diameter and subscript h denote handle. By substituting 0.4 for the handle's diameter then cirxumference of outer part is 
The rate of rotation will then be 1.81/1.256=1.441 rev/s
Similarly, circumference of inner part will be 
where subscript i represent inner. Substituting 0.1 for inner diameter then
The rate of rotation found for outer handle applies for inner hence speed will be 0.3142*1.441=0.453 m/s
Answer:
Density = Mass/volume. D= 60/30.Divide it and you'll get ur answer as 2
<h2>
Answers:</h2>
-The first direct detection of gravitational waves came in 2015
-The existence of gravitational waves is predicted by Einstein's general theory of relativity
-Gravitational waves carry energy away from their sources of emission
<h2>
Explanation:</h2>
Gravitational waves were discovered (theoretically) by Albert Einstein in 1916 and "observed" for the first time in direct form in 2015 (although the results were published in 2016).
These gravitational waves are fluctuations or disturbances of space-time produced by a massive accelerated body, modifying the distances and the dimensions of objects in an imperceptible way.
In this context, an excellent example is the system of two neutron stars that orbit high speeds, producing a deformation that propagates like a wave,<u> in the same way as when a stone is thrown into the water</u>. So, in this sense, gravitational waves carry energy away from their sources
.
Therefore, the correct options are D, E and F.
