Which of the following features of a telescope determines its light-gathering power?
a. the focal length of the primary lens
b. the focal length of the eyepiece
c. the diameter of the primary lens
d. length of the telescope tube
e. None of the other choices are correct.
c
You might also like to view...
Photoelectric Effect: What is the longest wavelength of light that can cause photoelectron emission from a metal that has a work function of 2.20 eV? (1 eV = 1.60 × 10-19 J, c = 3.00 × 108 m/s, h = 6.626 × 10-34 J ? s)
A. 417 nm B. 257 nm C. 344 nm D. 565 nm E. 610 nm
Which one of the following is the correct expression for the Heisenberg uncertainty principle?
A) ?py ?y ? h/2? B) ? py ?y ? h/2? C) ? py /?y ? h/2? D) ?y/? py ? h/2? E) None of the other answers is correct.
One mole of "o" gas is confined to volume V/2 by a thin membrane with a vacuum on the other side
You are standing in a moving bus, facing forward, and you suddenly move forward as the bus comes to an immediate stop. What force caused you to move forward?
A) force of gravity B) normal force due to your contact with the floor of the bus C) force due to static friction between you and the floor of the bus D) force due to kinetic friction between you and the floor of the bus E) no forces were responsible for your fall.