Physicshard · Past Paper
The magnifying power of a telescope is 10 and its length is 110 cm. What are the focal lengths of the lenses?
A100 cm, 10 cm
B55 cm, 55 cm
C110 cm, 10 cm
D90 cm, 20 cm
✓ Correct Answer: A — 100 cm, 10 cm
m = fo/fe = 10 and L = fo + fe = 110. Solving gives fo = 100 cm and fe = 10 cm.
Share this question
More from Physics
- Which of the following does not possess kinetic energy?
- What is the rate of change of displacement called?
- The ratio of displacement to distance for a moving object is:
- The velocity of a body increases from 5 m/s to 15 m/s while covering a distance of 20m. Find the acceleration.
- If a body of mass m starts falling from point A at height h, what is its velocity at point B which is at height h/2?