Physicsmedium · Past Paper
What is the power of a combination of two lenses with powers +2D and -1D in contact?
A+3 D
B+1 D
C-3 D
D-1 D
✓ Correct Answer: B — +1 D
The total power is the algebraic sum: P = P1 + P2 = 2 + (-1) = +1 D.
Share this question
More from Physics
- The force of gravitation between two bodies is F. If the mass of one body is doubled, the force becomes:
- When an object is immersed in a liquid, its apparent weight is:
- A force of 10 N acts on a body of mass 2 kg for 3 seconds. The change in momentum is:
- In a step-up transformer, the current in the secondary coil compared to the primary coil is:
- If a ray of light goes from water to air, its speed: