We are given with the data that the angle of velocity is above the negative axis. hence, the angle lies in the second quadrant with negative x axis and positive y axis. In this case, the x component is -12 cos 60 equal to -6 m/s while the y-component is 12 sin 60 equal to 6 sqrt of 3 m/s.
False (if the #s are lower the answer for power would also be lower)
Answer:
u = 88.54 m/s
Explanation:
Given that,
A discus thrower achieves a high throw of 100 m.
Angle of projection is 30°
We need to find the initial speed of the discuss. It is a cse of projectile motion. The maximum height reached by the discus is given by :

u is the initial speed of the discus
So,

So, the initial speed of the discus is 88.54 m/s.
(a) The y-component or vertical velocity is calculated using:
Vy = Vsin(∅)
(b) The x-component or horizontal velocity is calculated using:
Vx = Vcos(∅)
<h2>
Answer: U-238</h2>
Explanation:
Let's begin by explaining that for radioactive geological dating (also called radioisotope dating) in which radioactive impurities were selectively incorporated when the fossil materials were formed, it is very useful to compare it with a naturally occurring radioisotope having a known half-life.
Now, taking into account that the <u>fossils are millions and millions of years old, radioisotopes are needed that exceed this measure.
</u>
To understand it better:
The longer the half-life of a radioisotope, the greater its utility for estimating fossil ages or geological formations.
In this sense, uranium-238 (U238) has a half-life of 4,470 million years, therefore, it is among the most commonly used radioisotopes for fossil and geological dating.