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>
Answer: 750 kgm/s
Explanation:
Mass of object = 25 kg
Speed by which object moves =30 m/s. Linear momentum of the object = ?
Since momentum refers to the quantity of motion of the moving object,
Linear momentum = Mass x Speed
= 25kg x 30m/s
= 750 kgm/s
Thus, the linear momentum of the object is 750 kgm/s
Answer: 15.29
Explanation: there you go have a nice day (*^p^*)