Answer:
Explanation:
Given:
Initial mass of isotope (m₀) = 20 g
Half life of the isotope 
= (ln 4) years
The general form for the radioactive decay of a radioactive isotope is given as:
Where,
So, the equation is: 
At half-life, the mass is reduced to half of the initial value.
So, at 
. Plug in these values and solve for 'k'. This gives,
Hence, the equation for the mass remaining is given as:
To be careful towards what you do.
Force is a push or a pull of an object that causes the object to speed up, slow down, or stay in one place. In other words, a force is what causes an object to move. Friction and gravity are two types of forces that influence how an object moves.
Hope I can help you!
Answer:
5.09 x 10⁵ Nm²/C
Explanation:
The electric flux φ through a planar area is defined as the electric field Ε times the component of the area Α perpendicular to the field. i.e
φ = E A
From the question;
E = (8.0j + 2.0k) ✕ 10³ N/C
r = radius of the circular area = 9.0m
A = area of a circle = π r² [Take π = 3.142]
A = 3.142 x 9² = 254.502m²
Now, since the area lies in the x-y plane, only the z-component of the electric field is responsible for the electric flux through the circular area.
Therefore;
φ = (2.0) x 10³ x 254.502
φ = 5.09 x 10⁵ Nm²/C
The electric flux is 5.09 x 10⁵ Nm²/C
