Question

Wrap up question 1: What colors would be reflected by an orange tab if you placed it in red, green, or blue light? Justify your response with the results you had for red and yellow tabs in red, green, and blue light.

Wrap up question 2: If you have a yellow light source and every color filter to use, could you produce every other possible color? Explain.

Wrap up question 3: If an object is 20 cm from a lens and the image is formed 10 cm behind the lens, what is the focal length of the lens? Explain why the focal length isn’t 10 cm.

Short answer is ok， plz TYPE answer （no handwriting）Thank you！

Answer 1

1.orange tab in red will be dark red

orange tab in green will be yellowish red

orange tab in blue is light red.

an object show color which it reflects from electromagnetic spectrum. eg: orange tab reflects color in range near to wavelength of orange

red tab in red light is red

red tab in green is yellow

red tab in blue is pink

yellow tab in green is yellow

yellow tab in red is yellow

yellow tab in blue is combination of green and blue

these results shows an object show color which it reflects from electromagnetic spectrum. eg: orange tab reflects color in range near to wavelength of orange

2.yellow is combination of green and red lights. if we add blue light to this yellow it will become white, this is how we can simply change yellow to other color  

3.by using lens formula 1/f=1/u+1/v

u=-20(since measuring opposite of light ray) and v=10 (in direction of light ray),we will get f as 20.

if f=10 and object is in 20 (2f) image will form in 20(2f)) itself.not in this case as in question so f is not equal to 10