Home
Class 12
PHYSICS
Two discharge tubes have identical mater...

Two discharge tubes have identical material structure and the same gas is filled in them. The length of one tube is 10cm and that of th other tube is 20cm. Sparking starts in both the tubes when the potential difference between the cathode and the anode is `100 V`. If the pressure in the shorter tube is `1.0 mm` of mercury, what is the pressure in the longer tube?

Text Solution

Verified by Experts

`V = f(Pd), v_8 =P_8 d_8, v_L = P_l d_l `
` V_s/V_l = P_s/P_l xx d_s/d_l `
` rArr 100/100 = 10/20 xx 1mm/x `
` rArr 20/10 = 1mm/x `
` rArr x = 1mm/2 = 0.5mm ` .
Promotional Banner

Topper's Solved these Questions

  • ELECTRIC CURRENT THROUGH GASES

    HC VERMA|Exercise Objective 2|7 Videos

  • ELECTRIC CURRENT IN CONDUCTORS

    HC VERMA|Exercise Exercises|84 Videos

  • ELECTRIC FIELD AND POTENTIAL

    HC VERMA|Exercise Exercises|75 Videos

Similar Questions

Explore conceptually related problems

If the potential difference between the cathode and the target of Coolidge tube is 1.24xx10^(5)V , then the minimum wavelength of continuous X-rays is ______.

Figure shows the intensity-wavelength relations of X-rays coming from two different Coolidge tube. The solid curve represents the relation for the tube A in which the potential difference between the target and the filament is V_a and the atomic number of the target material is Z_A . These quantities are V_beta and Z_beta for the other tube. Then,

50% of the X-ray coming from a Coolidge tube is able to pass through a 0.1 mm thick aluminum foil. If the potential difference between the target and the filament is increased, the fraction of the X-ray passing through the same foil will be

The mean free path of electrons in the gas in a discharge tube is inversely proportional to the pressure inside it. The Crookes dark space occupies half the length of the discharge tube when the pressure is 0.02 mm of mercury. Estimate the pressure at which the dark space will fill the whole tube.

A capillary tube of radius 0.50 mm is dipped vertically in a pot of water. Find the difference between the pressure of the water in the tube 5.0 cm below the surface and the atmospheric pressure. Surface tension of water =0.075Nm^-1

A steel tube of length 1.00 m is struck at one end. A person with his ear close to the other end hears the sound of the blow twice one travelling through the body of the tube and the other through the air in the tube. Find the time gap between the two hearings.

The mean free path of the electrons in a discharge tube is 20 cm. The tube itself is 10cm long. What is the length of the Crookes dark space?

The mercury manometer consists if two unequal arms of equal cross section 1 cm^(2) and lenghths 100cm and 50cm. The two open ends are sealed with air in the tube at a pressure of 80cm of mercurey. Some amount of mercury is now introduced in the manometer through the stopcock connected to it. If mercury rises in the shorter tube to a lenght 10cm in steady state, find the length of the mercury column risen in the longer tube.

Figure shows a liquid being pushed out of a tube by pressing a piston. The area of cross section of the piston is 1.0 cm^2 and that of the tube at the outlet is 20 mm^2 . If the piston is pushed at a speed of 2cms^-1 . What is the speed of the outgoing liquid?

A thin tube of uniform cross section is sealed at both ends. It lies horizontally, the middle 5cm containing mercury and the parts on its two sides containing air at the same pressure p. when the tube is held at and angle of 60_(@) with the vertical, the length of the air column above and belw the mercury pellet are 46cm and 44.5cm respectively. Calculate the ressure - in centimeters of mercury, The timperature of the system is kept at 30_(@)C .

HC VERMA-ELECTRIC CURRENT THROUGH GASES-Exercise
  1. A molecule of a gas, filled in a discharge tube, gets ionized when an ...

    Text Solution

    |

  2. The mean free path of electrons in the gas in a discharge tube is inve...

    Text Solution

    |

  3. Two discharge tubes have identical material structure and the same gas...

    Text Solution

    |

  4. The constant A in the Richordson-Dushman equation is 60 xx 10^4 A m^(-...

    Text Solution

    |

  5. The saturation current from a thoriated-tungsten cathode at 2000 K is ...

    Text Solution

    |

  6. A Tungsten cathode and a thoriated-tungsten cathode have the same geom...

    Text Solution

    |

  7. If the temperature of a tungsten filament is raised from 2000 K to 201...

    Text Solution

    |

  8. The constant A in the Richardson-Dushman equation for tungsten is 60 x...

    Text Solution

    |

  9. A plate current of 10 mA is obtained when 60 volts are applied across ...

    Text Solution

    |

  10. The plate current in a diode is 20 mA when the plate voltage is 50 V o...

    Text Solution

    |

  11. The power delivered in the plate circuit of a diode is 1.0 W when the ...

    Text Solution

    |

  12. A triode valve operates at Vp = 225 V and Vg = - 0.5 V. The plate curr...

    Text Solution

    |

  13. Calculate the amplification factor of a triode valve which has plate r...

    Text Solution

    |

  14. The dynamic plate resistance of a triode valve is 10 kOmega. Find the ...

    Text Solution

    |

  15. Find the values of rp, mu and gm of a triode operating at plate voltag...

    Text Solution

    |

  16. The plate resistance of a triode is 8 kOmega and the transconductance ...

    Text Solution

    |

  17. The plate resistance and the amplification factor of a triode are 10 k...

    Text Solution

    |

  18. The plate current, plate voltage and grid voltage of a 6F6 triode tube...

    Text Solution

    |

  19. The plate current in a triode can be written as ip = k (Vg + (Vp)/(m...

    Text Solution

    |

  20. A triode has mutual conductance = 2.0 millimho and plate resistance =...

    Text Solution

    |