JAMB - Physics (1990 - No. 20)
An object which is 3cm high is placed vertically 10cm in front of a concave mirror. If this object produces an image 40cm from the mirror, the height of the image is
0.75cm
4.00cm
8.00cm
12.00cm
คำอธิบาย
\(\frac{\text {object height}}{\text{image height}}\) = \(\frac{\text {object distance}}{\text{image distance}}\)
\(\frac{3}{\text{image height}}\) = \(\frac{10}{40}\)
Image height = 12cm
\(\frac{3}{\text{image height}}\) = \(\frac{10}{40}\)
Image height = 12cm