Answer:
The equation for the object's displacement is 
Explanation:
Given:
m = 16 lb
δ = 3 in
The stiffness is:

The angular speed is:

The damping force is:

Where
FD = 20 lb
u = 4 ft/s = 48 in/s
Replacing:

The critical damping is equal:

Like cc>c the system is undamped
The equilibrium expression is:

The radius of a nucleus of hydrogen is approximately

, while we can use the Borh radius as the distance of an electron from the nucleus in a hydrogen atom:

The radius of a dime is approximately

: if we assume that the radius of the nucleus is exactly this value, then we can find how far is the electron by using the proportion

from which we find

So, if the nucleus had the size of a dime, we would find the electron approximately 500 meters away.
Answer:
1.61 second
Explanation:
Angle of projection, θ = 53°
maximum height, H = 7.8 m
Let T be the time taken by the ball to travel into air. It is called time of flight.
Let u be the velocity of projection.
The formula for maximum height is given by

By substituting the values, we get

u = 9.88 m/s
Use the formula for time of flight


T = 1.61 second