D. diamond, is the best option..
It is D because our eye lenses reflect the white light we see and it also reflects the light to a point to where we can see colors and objects clearly... Hope this helps out ^-^''
Answer:
- 3 cm
Explanation:
From the mirror formula;
1/f = 1/v + 1/u ; where f is the focal length, v is the image distance, and u is the object distance.
1/-4.5 = 1/9 + 1/v
1/v = -1/4.5 - 1/9
= -1/3
Therefore;
v = -3 cm
Hence;
Image distance is - 3cm
Answer:
Frequency=10 Hz
Period=0.1 s
Explanation:
Frequency of a wave is the number of complete cycles per unit time. Usually, frequency is cycles per second, with unit as Heartz
Given cycles of the wave as 200 and time as 20 seconds
Frequency=200÷20=10 cycles per second
Therefore, frequency is 10 Hz
Period is usually the reviprocal of frequency hence reciprocal of 10 Hz will be 1/10=0.1 s