Explanation:
Mirrors consist of reflecting surfaces that reflect light.
Reflection is a phenomenon of light wave (but also of other types of waves) in which a ray of light hits a surface, and then it bounces back into the original medium at a certain angle.
The direction of the reflected ray is determined by the law of reflection:
- The incident ray, the reflected ray and the normal to the surface all lie in the same plane
- The angle of reflection is equal to the angle of incidence (where both angles are measured between the ray and the normal to the surface)
A plane mirror is a type of mirror consisting of a straight surface. As a result, light incident perpendicular to the surface is reflected back exactly in the opposite direction.
The image formed by a plane mirror is:
- The same size as the object
- Virtual (it is located behind the mirror)
- Laterally inverted
- Upright
Answer:
A = 0.325 Bq
Explanation:
given,
half life of ¹⁴C = 5730 years
fixed fraction 1.30 × 10⁻¹² of ¹²C
half life = 5730 years
T_{1/2} = 5730 x 365 x 24 x 60 x 60
= 1.807 x 10¹¹ s
radioactive decay constant
λ =
λ =
λ = 3.835 x 10⁻¹² /s
number of atom
mass m = 1.30 g
n = 6.524 x 10²²
Number of ¹⁴C atoms in 1.3 g of sample N ' =
= 1.30 × 10⁻¹² x 6.524 x 10²²
= 8.482 x 10¹⁰
Required activity, A = λ N
A = 3.835 x 10⁻¹² x 8.482 x 10¹⁰
A = 0.325 Bq