Answer:
The answer is B
Explanation: Greenhouse gases must be able to change their vibrational state in order to absorb infrared radiation or heat. SO therefore helium is not one of them.
Hope this helps:)
Depends on the elasticity and density of the medium through what it is traveling <span> </span>
Answer:
v = 10.84 m/s
Explanation:
using the equation of motion:
v^2 = (v0)^2 + 2×a(r - r0)
<em>due to the hammer starting from rest, vo = 0 m/s and a = g , g is the gravitational acceleration.</em>
v^2 = 2×g(r - r0)
v = \sqrt{2×(-9.8)×(4 - 10)}
= 10.84 m/s
therefore, the velocity at r = 4 meters is 10.84 m/s
B is the correct answer
y=Asin(wt-kx)
A=amplitude
f=frequency
x=wavelength
since refraction is not on the wave formula,then option B is the correct answer
