题目

英语翻译
28 Parallel wave fronts incident on an opening in a
barrier are diffracted.For which combination of
wavelength and size of opening will diffraction
effects be greatest?
(1) short wavelength and narrow opening
(2) short wavelength and wide opening
(3) long wavelength and narrow opening
(4) long wavelength and wide opening
32 A photon of light traveling through space with a
wavelength of 6.0 × 10–7 meter has an energy of
(1) 4.0 × 10–40 J (3) 5.4 × 1010 J
(2) 3.3 × 10–19 J (4) 5.0 × 1014 J
34 The charge of an antistrange quark is
approximately
(1) +5.33 × 10–20 C (3) +5.33 × 1020 C
(2) –5.33 × 10–20 C (4) –5.33 × 1020 C
35 What fundamental force holds quarks together
to form particles such as protons and neutrons?
(1) electromagnetic force
(2) gravitational force
(3) strong force
(4) weak force
39 What is the magnitude of the force needed to keep a 60.-newton rubber block moving across level,

提问时间：2020-07-24

答案