v = fλ
v = velocity, f = frequency, λ = wavelength
f = 1/T
f = frequency, T = period
v = fλ = λ/T
Given values:
λ = 4.5m, T = 0.007s
v = 4.5/0.007
v = 643m/s
Round to 2 significant figures:
v = 640m/s
v = I ⁄ T
v= 4.5 ⁄ 0.007
v = 642.9 m/s
Explanation:
Options B and C: Star B is moving toward Earth. AND Star B is moving toward Earth.
Explanation:
Trust meh pleasee