Period: 1/Frequency
1/457 = 0.002188 seconds
Round it to 0.0022 seconds
The answer is D
Answer:
See the explanation below.
Explanation:
This is because the vacuum chamber removes all the air contained and for this reason, there is no force that opposes the movement of the feather when falling. We must remember that the free fall equation of kinematics is not a function of the mass of an object.

where:
Vf = final velocity [m/s]
Vo = initial velocity [m/s]
g = gravity acceleration [m/s²]
t = time [s]
As we can see the mass of the object is not included in the equation.
Answer:
A = B = C > D
Explanation:
Work done to stop the disc is given as


so we have
(a) –2 rad/s, 5 rad/s;
(b) 2 rad/s, 5 rad/s;
(c) –2 rad/s, –5 rad/s; and
(d) 2 rad/s, –5 rad/s.
So we have


so we have
A = B = C > D