Home
Class 12
PHYSICS
Fluorescence starts in a discharge tube ...

Fluorescence starts in a discharge tube when the pressure of gas inside the tube ( in terms of height of mercury column) is :

A

10 mm

B

5 mm

C

0.01 mm

D

`10^4 mm`

Text Solution

Verified by Experts

The correct Answer is:
C
Promotional Banner

Similar Questions

Explore conceptually related problems

What is the source of anode rays in discharge tube?

An open-end manometer was used to determine the pressure of a gas present in a container. It was found that the height of mercury level in the arm attached to the gas-filled container was 4 cm higher than that in the open ene arm. If the atmospheric pressure was measured to be 76 cm Hg, then what will be the pressure of the gas inside the container in atm unit?

Explain why cathode rays are produced only at very low pressure of a gas inside the discharge tube.

Why is the upper meniscus of mercury convex in a glass tube?

The cross-sectional area of the left limb of a U-tube is one-third of that of its right limb. It contains some mercury. The empty space in the left limb measures to 40 cm. If water is poured to fill it up, then find the rise of the mercury column in the right limb. (Specific gravity of mercury = 13.6)

Water is flowing in streamline motion through a horizontal tube. The pressure at a point in the tube is p where the velocity of flow is v. At another point, where the pressure is p/2, the velocity of flow is [density of water =rho ]