Question

A 4.0cm tall candle is positioned 28.0cm from thin convex lens with a 20.0cm focal length along the meter stick of an Optical Bench Kit available in many physics classrooms. Identify the true statement. A. The image distance is 70.0cm and image height is 10.0cm. OB. The image distance is 70.0cm and image height is 2.5cm. C. The image distance is 120.cm and image height is 10.0cm. D. The image distance is 120.cm and image height is 2.5cm. O E. The image distance is 120.cm and image height is 1.6cm.

Answer 1

image is inverted and image height 10 cm and image distance is 70 cm

option A is correct

Step-by-step explanation:

given data

tall = 4 cm

candle position = 28.0 cm

focal length = 20 cm

to find out

true statement

solution

we apply here lens formula for convex lens

1/f = 1/p + 1/q

here p = 28 f = 20 so q will be

1/20 = 1/28 + 1/q

q = 70 cm

so magnification will be

M = - q/p = h1/h2 .........1

here h1 is image height

and h2 is object height that is 4 cm

so from equation 1

- 70 / 28 = h1 / 4

h1 = -10 cm

so image is inverted and height 10 cm

option A is correct