To establish the age of a rock or a fossil, researchers use some type of clock to determine the date it was formed. Geologists commonly use radiometric dating methods, based on the natural radioactive decay of certain elements such as potassium and carbon, as reliable clocks to date ancient events.
Answer:
8.13secs
Explanation:
From the question weal are given
Height H =324m
Required
time it takes to drop t
Using the equation of motion
H = ut + 1/2gt²
Substitute the given values
324 = 0(t)+1/2(9.8)t²
324 = 1/2(9.8)t²
324 = 4.9t²
t² =324/4.9
t² = 66.12
t = √66.12
t = 8.13secs
Hence the time taken to drop is 8.13secs
Answer:
a) 4.9*10^-6
b) 5.71*10^-15
Explanation:
Given
current, I = 3.8*10^-10A
Diameter, D = 2.5mm
n = 8.49*10^28
The equation for current density and speed drift is
J = I/A = (ne) Vd
A = πD²/4
A = π*0.0025²/4
A = π*6.25*10^-6/4
A = 4.9*10^-6
Now,
J = I/A
J = 3.8*10^-10/4.9*10^-6
J = 7.76*10^-5
Electron drift speed is
J = (ne) Vd
Vd = J/(ne)
Vd = 7.76*10^-5/(8.49*10^28)*(1.60*10^-19)
Vd = 7.76*10^-5/1.3584*10^10
Vd = 5.71*10^-15
Therefore, the current density and speed drift are 4.9*10^-6
And 5.71*10^-15 respectively
Anything that has mass has weight and anything that has weight has mass simple.
