Answer:
wavelength is 121.58 nm
Explanation:
given data
wavelength = 230 nm = 230 x m
kinetic energy = 3.35 × J
to find out
wavelength of light that triple the maximum kinetic energy of the electron
solution
we know here Einstein's photo electric equation that is given below
hc / λ = φ + K(maximum)
and here φ will be
φ = (hc) / λ - K(max
imum)
put here h = 6.626 x J.s
and 3.0 x m/s
so φ = (6.626 x )( 3.0 x ) / ( 230 x ) - 3.35 x
φ = 6.2995 x J
so here we have given triple the maximum kinetic energy
so
hc / λ = φ + K(maximum)
λ = hc / ( φ + K(maximum) )
λ = (6.626 x )( 3.0 x ) / ( 6.2995 x + 3 ( 3.35 x ))
λ = 1.215817 ×
so wavelength is 121.58 nm
<span>This
is because astronomers have discovered that
the Crab Nebula is 6500 light years from earth. This means it takes 6500 earth years
for light to get from the Crab Nebula to
earth. Therefore, if we are able to observe the
Crab Nebula and beyond it then it means that earth has been in existence for 6500 years and
over. </span>
Answer:
640 m.
Explanation:
The following data were obtained from the question:
Acceleration (a) = –20 m/s/s
Time (t) = 8 s
Final velocity (v) = 0 m/s
Distance (s) =.?
Next, we shall determine the initial velocity (u) of the car. This can be obtained as follow:
Acceleration (a) = –20 m/s/s
Time (t) = 8 s
Final velocity (v) = 0 m/s
Initial velocity (u)
a = (v – u) / t
–20 = (0 – u) / 8
–20 = – u / 8
Cross multiply
–20 × 8 = – u
– 160 = – u
Divide both side by – 1
u = – 160 / – 1
u = 160 m/s
Finally, we shall determine the distance travelled by the car before stopping as follow:
Time (t) = 8 s
Final velocity (v) = 0 m/s
Initial velocity (u) = 160 m/s
Distance (s) =.?
s = (v + u)t /2
s = (0 + 160) × 8 /2
s = (160 × 8) /2
s = 1280 / 2
s = 640 m
Therefore, the car travelled 640 m before stopping.