An object 15cm high is 30cm from pin-hole camera. If the height of the image formed at the back of the camera is 10cm, the image distance is
20cm
45cm
54cm
63cm
70cm
Correct answer is A
\(\frac{\text{image height}}{\text{object height}}\) = \(\frac{\text{image distance}}{\text{object distance}}\)
\(\frac{10}{15}\) = \(\frac{\text{image distance}}{30}\)
image distance = 20cm