As radiation enters a solid or liquid, the light waves are absorbed and reflected by the atoms. the resulting reflection from an atom can be in any direction and is random. you can understand opacity in terms of the scattering of radiation. The more opaque, the more scattering.
(The truth is far more complicated than this, check out Richard Feynmans lectures on "Quantum Electro Dynamics" to learn the reality of it. )
Answer:
Explanation:
Magnetic field due to a long current carrying conductor
μ₀ / 4π x 2i / r ( i = current , r = distance of point from wire )
= 10⁻⁷ x 2 x 120 / 6.4 ( i = 120 A , r = 6.4m )
= 37.5 x 10⁻⁷ T .
= 3. 75 X 10⁻⁶ T .
= 3.75 µT.
b )
The direction of this field will be horizontal hence it will affect magnetic needle.
Answer:
For every action, there is an equal and opposite reaction.
Explanation:
Let's say I threw a ball on the wall. The image shows the instance the ball comes into contact with the wall.
If you would look at the image above,
- F1 and F2 are acting in opposite directions.
- They both have the same magnitude too.
F1 is the force of the ball on the wall (action force) and F2 is the force of the wall on the ball (reaction force). This is called an action-reaction pair.
Ans: Radiocarbon dating uses carbon isotopes.
Radiocarbon dating relies on the carbon isotopes carbon-14 and carbon-12. Scientists are looking for the ratio of those two isotopes in a sample. Most carbon on Earth exists as the very stable isotope carbon-12, with a very small amount as carbon-13.