JAMB - Physics (2017 - No. 16)
Calculate the height of the image formed by a pinhole camera of length 12cm used to photograph an object 60cm away from the hole and 70cm high
10 cm
16 cm
5 cm
14 cm
解释
Magnification = \(\frac{\text{Length of camera}}{\text{distance of object from pin hole}}\)
m = \(\frac{12}{60}\)
= 0.2
Also magnification m = \(\frac{\text{Height of image}}{\text{Height of object}}\)
∴ Height of image = m × height of object
= 0.2 × 70
= 14cm
m = \(\frac{12}{60}\)
= 0.2
Also magnification m = \(\frac{\text{Height of image}}{\text{Height of object}}\)
∴ Height of image = m × height of object
= 0.2 × 70
= 14cm