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:
Statement 2 is wrong
Explanation:
To check the statements in this exercise, let's describe the main properties of electromagnetic waves. Let's describe the characteristics
* they are transverse waves
* formed by the oscillations of the electric and magnetic fields
* the speed of the wave is the speed of light
with these concepts let's review the final statements
1) True. Formed by the oscillation of the two fields
2) False. They are transverse waves
3) True. Can travel by vacuum as they are supported by oscillations of the electric and magnetic fields
4) True. They all have the same speed of light
Statement 2 is wrong
You can mark, lift and clean a ball on the green, but it's a violation to do so when another ball is in motion, as your ball might influence the outcome of that stroke. You can also mark and clean your ball in some instances when it's off the green: cleaning it, for example, just to the point where you can identify it.
Answer:
58.5 meters
Explanation:
1. Find your formula. Use distance = speed x time for this problem
2. Plug in the given information. d (for distance) = 9m/s^2 * 6.5 s
3. Multiply number AND units. d = 58.5m
4. Check to make sure units & numbers make sense. In this case check that the answer is a lot bigger than what we stated with and that our units go with distance
Because when you spill water on it, the reflection comes from the surface of the water, not the ground glass.
