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:)
Answer:
![m_2 = 23 kg](https://tex.z-dn.net/?f=m_2%20%3D%2023%20kg)
Explanation:
As we know that the tension in two strings are
![T_2 = 111 N](https://tex.z-dn.net/?f=T_2%20%3D%20111%20N)
![T_4 = 222 N](https://tex.z-dn.net/?f=T_4%20%3D%20222%20N)
now we have
![F_{net} = ma](https://tex.z-dn.net/?f=F_%7Bnet%7D%20%3D%20ma)
so we can say
![(m_1 + m_2)a = T_2](https://tex.z-dn.net/?f=%28m_1%20%2B%20m_2%29a%20%3D%20T_2)
![(12 + m_2)a = 111](https://tex.z-dn.net/?f=%2812%20%2B%20m_2%29a%20%3D%20111)
also we have
![(m_1 + m_2 + m_3 + m_4) a = T_4](https://tex.z-dn.net/?f=%28m_1%20%2B%20m_2%20%2B%20m_3%20%2B%20m_4%29%20a%20%3D%20T_4)
![(12 + m_2 + 15 + 20) a = 222](https://tex.z-dn.net/?f=%2812%20%2B%20m_2%20%2B%2015%20%2B%2020%29%20a%20%3D%20222)
now divide two equations
![\frac{222}{111} = \frac{47 + m_2}{12 + m_2}](https://tex.z-dn.net/?f=%5Cfrac%7B222%7D%7B111%7D%20%3D%20%5Cfrac%7B47%20%2B%20m_2%7D%7B12%20%2B%20m_2%7D)
![2m_2 + 24 = 47 + m_2](https://tex.z-dn.net/?f=2m_2%20%2B%2024%20%3D%2047%20%2B%20m_2)
![m_2 = 23 kg](https://tex.z-dn.net/?f=m_2%20%3D%2023%20kg)
As the density of the unknown substance is 0.68g/0.8ml = 0.85g/ml, it is less dense than the maple syrup at 1.33g/ml and will float.
Answer: search it on browser
The magnitude of the electrostatic force is 0.09 N, and the force is attractive
Explanation:
The strength of the electrostatic force acting on a charged particle is given by
![F=qE](https://tex.z-dn.net/?f=F%3DqE)
where
q is the charge
E is the magnitude of the electric field
For the charge in this problem, we have:
is the electric field
is the charge
Therefore, the force experienced by this charge is
![F=(-2.0\cdot 10^{-6})(4.5\cdot 10^4)=-0.09 N](https://tex.z-dn.net/?f=F%3D%28-2.0%5Ccdot%2010%5E%7B-6%7D%29%284.5%5Ccdot%2010%5E4%29%3D-0.09%20N)
And the negative sign means that the force is attractive: in fact, the charge is negative, while the charge that is producing the field is positive (because the electric field points outward), therefore the negative charge is attracted towards the positive charge that is generating the field.
Learn more about electrostatic force:
brainly.com/question/8960054
brainly.com/question/4273177
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