Why do single-dish radio telescopes have poor resolving power compared to optical telescopes of the same diameter?
Answer: Because the size of diffraction fringes is proportional to the wavelength of light being focused, and radio waves have longer wavelengths than visible light.
You might also like to view...
Radioactive dating methods and other dating methods indicate that hominids have been on Earth for about
A) 15 billion years. B) 5 billion years. C) 5 million years. D) 100,000 years. E) 5000 years.
From what height above the surface of the earth should an object be dropped to initially experience an acceleration of 0.9200g? The radius of the earth is 6.38 × 106 m
A) 272 km B) 260 km C) 554 km D) 510 km
The force due to gravity has the mathematical form 
.
a. True
b. False
Indicate whether the statement is true or false
In ultrasonic nondestructive testing with the pulse echo technique, a crack is detected by the _________ultrasonic waves.
Fill in the blank(s) with the appropriate word(s).