Answer:
the only one of these materials that allows studying processes of a very long period of time is Uranium 238
Explanation:
In a radioactive material, half of the atoms decay each life period, in carbon 14 this period T = 5730 years, so for a time of 40,000 years there are 7 life periods, so there are very few atoms left without decomposing .
To study older samples, materials with a longer life period are needed, let's show the visa time
²³⁸U T= 4.5 10¹⁰ years
⁹¹Rb T = 58 s
¹³¹I T= 8.04 days
⁶⁰Co T= 5.27 years
Therefore, the only one of these materials that allows studying processes of a very long period of time is Uranium 238
The frequency is the number of waves per unit time
Тнe Anѕwer
-It was Ernest Rutherford
Answer:
Turns ratio=108, Pin= 110.5 W, Current ratting= 920mA
Explanation:
Vp=120 V(rms)
Vs=13,000 V (rms)
Is = 8.50*10^-3 V(rms)
a.
secondary to primary turn ration:
Ns/Np=Vs/Vp
=
=
= 108
b.
Is=8.50 mA (rms)
As Vs= 13,000V (rms)
For ideal transformer
Pin=Pout______(1)
Pout= Is*Vs (put in equ 1)
Pi=Is*Vs
Pi=(8.50*10^-3)*(13,000) W
Pi=110.5 W
Power supplied will be 110.5 W.
c.
We have to find the current passing through primary circuit to find current rating of fuse in primary circuit.
For ideal case
Ip*Vp= Is*Vs
Ip=
Ip= (13000*8.5*10^-3)/120
Ip=920 mA
In primary circuit fuse current rating will be 920 mA.
Answer:
<h2>
Answer⤵</h2><h3><u>i</u><u>)</u><u>The first law of reflection states that the incident ray, the reflected ray, and the normal to the surface of the mirror, all lie in the same plane. </u></h3><h3><u>i</u><u>i</u><u>)</u><u>The second law of reflection states that the angle of reflection is equal to the angle of incidence. Both angles are measured with respect to the normal to the mirror.</u></h3>