Answer:
Time taken, 
Explanation:
It is given that, a small metal ball is suspended from the ceiling by a thread of negligible mass. The ball is then set in motion in a horizontal circle so that the thread’s trajectory describes a cone as shown in attached figure.
From the figure,
The sum of forces in y direction is :


Sum of forces in x direction,

.............(1)
Also, 
Equation (1) becomes :

...............(2)
Let t is the time taken for the ball to rotate once around the axis. It is given by :

Put the value of T from equation (2) to the above expression:


On solving above equation :

Hence, this is the required solution.
Setting up an integral of
rotation is used as a method of of calculating the volume of a 3D object formed
by a rotated area of a 2D space. Finding the volume is similar to finding the
area, but there is one additional component of rotating the area around a line
of symmetry.
<span>First the solid of revolution
should be defined. The general function
is y=f(x), on an interval [a,b].</span>
Then the curve is rotated
about a given axis to get the surface of the solid of revolution. That is the
integral of the function.
<span>It all depends of the
function f(x), which must be known in order to calculate the integral.</span>
Energy is transferred in a wave
Energy is transferred, but mass is not.
Answer: The 5 uses of mechanical energy are: 1) Hammering a nail
2) Using Dart gun 3) Moon 4) Hydropower plant 5) Sharping a pencil.