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.
Answer: A light bulb can be all of the following except option C (a consumer product if it is used to light the office of the board of directors.)
Explanation:
Products are classified as being BUSINESS or CONSUMER products according to the buyer's intended use of the product.
-Consumer products: these are sold goods that are used for personal, family, or household use. The intention of the buyer is for the products to satisfy his personal needs and desires. Example of some of the consumer products include: toothpaste, eatables and clothes.
Business products: products that are not for personal use but for the manufacturing of other goods are called business products.
Therefore a bulb is not serving as a personal use when used to light the office of the board of directors rather it's serving as a business product .
Answer:
C. The decrease in speed as the wave approaches shore.
Explanation:
The waves break when approaching the shore because the depth decreases. Thus, the wave travels more slowly and increases its height. There comes a time when the part of the wave on the surface travels faster than the one that travels under water, the ridge destabilizes and falls against the ground.