Problem 11 Whic a single thin lens? (5 pts) h of these statements correctly desc

Question

Problem 11 Whic a single thin lens? (5 pts) h of these statements correctly describe the images formed by an object placed in front of 1. 2. 3. 4. Real images are always enlarged Real images are always inverted Virtual images are always upright Convex lenses never produce virtual images a) 1 and 3 b) 2 and 3 c) 2 and 4 d) 2,3 and 4 e) 1,2 and 3 1 4 only Problem 12 List the waves of the electromagnetic spectrum in order of Longest to Shortest Wavelength. Name a practical use for three of the different types of waves (10pts)

Explanation / Answer

1) A convex lens form both real and virtual images.

It forms real images when the object is placed beyond the focus of the lens.

It can form a virtual image only when object is placed between the focus and optic center of the lens.

A real image is always inverted while virtual image is always upright.

In the case of convex lens , image formed when the object lies beyond the center of curvature is diminished , real and inverted. In the remaining cases image may be equal to or larger than the object.

So only statements 2 and 3 are correct . So option b is correct.

2) Electromagnetic waves are arranged in the order of decreasing wavelength as follows.

1. Radio waves 2. Micro waves 3. Infrared rays 4. Visible light 5. Ultraviolet rays 6. X rays 7. Gamma rays.

Radio waves have longest wavelength while gamma rays have shortest wavelength.

Uses :

UltraViolet Rays :

1. They are used to detect forged bank notes.

2. They are used in ( UV ) lamps in hospitals in the operating rooms to kill germs.

  Micro Waves:

1. They are used in remote sensing devices.

2. They are used for transmitting information because they can pass through smoke , fog and even rain.

3. They are used to cook food in micro ovens .

  Infrared Rays :

1. Most the TV remotes use Infrared Rays.

2. They are used in night vision camers and security cameras

Related Questions

Navigate

• Browse (All)
• Browse P
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.