Wave Motion (Physics)

Total Questions: 44

41. Television viewers using dish antenna to receive satellite signals do not receive signals during rain because: [U.P.P.C.S. (Pre) 2017]

1. of small size of antenna.

2. rain droplets absorb the energy of radio waves.

3. rain droplets disperse the energy of radio waves from their original direction.

Which of the above statements are correct?

Correct Answer: (d) 1, 2, and 3
Solution:

During rain, radio waves collide with raindrops partly or completely and converted into thermal energy absorbing the energy of radio waves.

Rain drops are also capable of disturbing the basic direction of energy of the radio waves Due to this reason, there is difficulty in receiving satellite signals during rain. Radio signals become weak during rain which can not be received by small antenna.

42. Following rays are used in the diagnosis of intestinal diseases: [43สณแตˆ B.P.S.C. (Pre) 1999]

Correct Answer: (a) X-rays
Solution:

X-rays are a form of electromagnetic radiations, which are used in the diagnosis of intestinal diseases.

43. CT Scan is done by using- [U.P.P.C.S. (Mains) 2011]

Correct Answer: (d) X-Rays
Solution:

CT scan or computed tomography are special X-rays tests that produce cross-sectional images of the body using X-rays and a computer.

44. Which of the following was invented by Wilhelm Rontgen? [U.P.P.C.S. (Pre) 2018]

Correct Answer: (b) X-Ray Machine
Solution:

X-ray, a type of electromagnetic waves was discovered by Wilhelm Rontgen, with wavelengths in the range of 0.01 to 10 nanometres. These rays are extensively used in the field of medical and industries.