Answer:
The period of motion of new mass T = 0.637 sec
Explanation:
Given data
Mass of object (m) = 9 gm = 0.009 kg
Δx = 3.5 cm = 0.035 m
We know that spring force is given by
F = m g
F = 0.009 × 9.81 = 0.08829 N
Spring constant


k = 2.522 
New mass
= 26 gm = 0.026 kg
Now the period of motion is given by


T = 0.637 sec
This is the period of motion of new mass.
The free-body diagram of the forces acting on the flag is in the picture in attachment.
We have: the weight, downward, with magnitude

the force of the wind F, acting horizontally, with intensity

and the tension T of the rope. To write the conditions of equilibrium, we must decompose T on both x- and y-axis (x-axis is taken horizontally whil y-axis is taken vertically):


By dividing the second equation by the first one, we get

From which we find

which is the angle of the rope with respect to the horizontal.
By replacing this value into the first equation, we can also find the tension of the rope:
Wavelength = speed / frequency
(345 m/s) / (20,000 Hz) = 0.017 m
Answer:
Relativistic velocity is of the order of 1/10th of the velocity of light
Explanation:
We define relativistic speed (or velocity) as a speed that is a significant fraction of the speed of light: c = 3*10^8 m/s
Such that for these speeds, the special relativity theory starts to apply (the relativity effects starts to apply).
Usually, we define relativistic speeds as those that are of the order (or larger) of c/10, which is one-tenth of the speed of light.
Then the correct option is C:
Relativistic velocity is of the order of 1/10th of the velocity of light