Answer:
THE LENGTH OF THE AIR COLUMN IS 9.5 CM
Explanation:
Taking the atmospheric pressure to be 760 mmHg;
When the capillary tube is held horizontally, the pressure of the tube is 760 mmHg
when the capillary tube is held vertically, the pressure increases by 4 cm = 40 mm
The new pressure of the tube is hence, 760 + 40 mmHg = 800 mmHg
Using the pressure forlmula;
P1 V1 = P2 V2
P1 A1 L1 = P2 A2 L2
where A1 and A2 is the area of the capillary tube and it is equal, it cancels out.
P1 l1 = P2 l2
l2 = P1 l1 / P2
l2 = 760 * 10 / 800
l2 = 9.5 cm
The length of the air in the tube is 9.5 cm.
Answer:
b Fuel for fusion reactors can be extracted from ocean water.
Explanation:
The fuel is deuterium, which makes up 0.02% of the hydrogen atoms in water. The oceans contain more than a billion cubic kilometres of water, so that's a lot of deuterium.
a is wrong. The fuel for fusion reactors is deuterium.
c is wrong. There is much research, but there are no large-scale fusion reactors in operation.
d is wrong. Fusion reactors do not produce radioactive waste as spent fuel. Most of the radioactive waste would be the reactor core itself.