The correct option is DISPERSION OF LIGHT AS IT ENTERS EARTH'S ATMOSPHERE. Scientists use astronomical spectrometer to analyse the composition of the sun and the stars. Astronomical spectrometer works on the basis of dispersion of light as it enters the earth's atmosphere.
Answer:
p2 = 9.8×10^4 Pa
Explanation:
Total pressure is constant and PT = P = 1/2×ρ×v^2
So p1 + 1/2×ρ×(v1)^2 = p2 + 1/2×ρ×(v2)^2
from continuity we have ρ×A1×v1 = ρ×A2×v2
v2 = v1×A1/A2
and
r2 = 2×r1
then:
A2 = 4×A1
so,
v2 = (v1)/4
then:
p2 = p1 + 1/2×ρ×(v1)^2 - 1/2×ρ×(v2)^2 = p1 + 1/2×ρ×(v1)^2 - 1/2×ρ×(v1/4)^2
p2 = 3.0×10^4 Pa + 1/2×(1000 kg/m^3)×(12m/s)^2 - 1/2×(1000kg/m^3)×(12^2/16)
= 9.75×10^4 Pa
= 9.8×10^4 Pa
Therefore, the pressure in the wider section is 9.8×10^4 Pa
Answer:
Explanation:
Remark
If both are trying to get the box into storage and they can only use lifting to do it, then Jude won't be able to do it. This assumes they cannot slide the boxes. Jude is not using enough force to overcome gravity so the box will just sit.
On the other hand Jamel is putting enough force to not only lift the box but it will move upwards against gravity. If we ignore that fact, then Jamel will get his box into storage.
Answer: A
Answer:
it increases by a factor 1.07
Explanation:
The peak wavelength of an object is given by Wien's displacement law:
(1)
where
b is the Wien's displacement constant
T is the temperature (in Kelvins) of the object
given the relationship between frequency and wavelength of an electromagnetic wave:
where c is the speed of light, we can rewrite (1) as
So the peak frequency is directly proportional to the temperature in Kelvin.
In this problem, the temperature of the object changes from
to
so the peak frequency changes by a factor
Answer:
D) magnetic attraction
Explanation:
Mixture consists of sulfur powder and iron filings . The former is non magnetic and the later is magnetic material . The best way to separate them is to use a magnet . This method is called magnetic separation method . A magnet will attract the iron filling but the sulfur will remain un-attracted . Thus, the two will get separated from each other.
