Question

Green light shines through a 130-mm-diameter hole and is observed on a screen.if the hole diameter is increased by 20%, does the circular spot of light on the screen decrease in diameter, increase in diameter, or stay the same?

Answer 1

Increase in diameter

Step-by-step explanation:

It is given that, Green light shines through a 130-mm-diameter hole and is observed on a screen.

Initial diameter,
`d_i=130\ mm`

If the bole diameter is increased by 20 %, then the increased diameter can be calculated by finding 20% of the initial diameter.

`d_f=(130* 120)/(100)`

`d_f=156\ mm`

Hence, it is clear that the circular spot of light on the screen increase in diameter.

Hence, the correct option is (b) " increase in diameter ".

Answer 2

We are given
diameter of hole = 130 mm

If the hole diameter is increased by 20%, the circular spot of light on the screen will increase in diameter. This is one of the wave properties of light. The waves are propagated as spherical waves when going through holes.