Answer:
proof in explanation
Explanation:
First, we will calculate the number of half-lives:
where,
n = no. of half-lives = ?
t = total time passed = 2100 million years
= half-life = 700 million years
Therefore,
Now, we will calculate the number of uranium nuclei left ():
and the rest of the uranium nuclei will become thorium nuclei ()
dividing both:
<u>Hence, it is proven that after 2100 million years there are seven times more thorium nuclei than uranium nuclei in the rock.</u>
The time spent in the air by the ball at the given momentum is 6.43 s.
The given parameters;
- <em>momentum of the ball, P = 0.9 kgm/s</em>
- <em>weight of the ball, W = 0.14 N</em>
The impulse experienced by the ball is calculated as follows;
where;
is impulse
is change in momentum
The time of motion of the ball is calculated as follows;
Thus, the time spent in the air by the ball at the given momentum is 6.43 s.
Learn more here:brainly.com/question/13468390
Answer: silicon,or maybe none.
Explanation: I searched it up not really sure sorry
Complete Question
A thin, horizontal, 12-cm-diameter copper plate is charged to 4.4 nC . Assume that the electrons are uniformly distributed on the surface. What is the strength of the electric field 0.1 mm above the center of the top surface of the plate?
Answer:
The values is
Explanation:
From the question we are told that
The diameter is
The charge is
The distance from the center is
Generally the radius is mathematically represented as
=>
=>
Generally electric field is mathematically represented as
substituting values
During convection of air currents, cool air sinks. <em>(b)</em>