An object is placed 100 cm in front of a lens of focal length 20 cm. A second lens is placed 15 cm past the first lens. The second lens has a focal length of 40 cm. Where is the final image formed?

A)

25 cm in front of the second lens
B)

8 cm in front of the second lens
C)

8 cm after the second lens
D)

10 cm after the second lens
E)

25 cm after the second lens


C

Physics & Space Science

You might also like to view...

What does this photograph show?

A) It is a picture of our own Milky Way Galaxy. B) It is a picture of the Andromeda galaxy, located about 2.5 million light-years away. C) It is a picture of a cloud of gas known as the Orion Nebula. D) It is a picture of our own solar system. E) It is a picture of a young star in the process of being born.

Physics & Space Science

In a double-slit experiment, the slit separation is 2.0 mm, and two wavelengths, 750 nm and 900 nm, illuminate the slits simultaneously. A screen is placed 2.0 m from the slits

At what distance from the central maximum on the screen will a bright fringe from one pattern first coincide with a bright fringe from the other? A) 1.5 mm B) 3.0 mm C) 4.5 mm D) 6.0 mm E) 9.0 mm

Physics & Space Science

The intensity at a distance of 6.0 m from a source that is radiating equally in all directions is 6.0 × 10-10 W/m2. What is the intensity level in dB? The threshold of human hearing is 1.0 × 10-12 W/m2

A) 18 dB B) 23 dB C) 28 dB D) 32 dB

Physics & Space Science

Suppose we have a certain length of wire that we would like to wind around a cylindrical form in a single layer of closely spaced turns to make it more compact, and we would like to minimize the inductance of the resulting coil. All the available forms have a small enough radius that the length of the coil will be much larger than its radius. Given this, we should choose the form with

A. The smallest radius. B. The largest radius. C. Any radius (the inductance will be the same). D. One needs more information to answer the question.

Physics & Space Science