The Jolly's Bulb Apparatus Experiment Viva Questions
1. What is the name of the
instrument used for measuring atmospheric pressure?
Barometer
2. Does the atmosphere pressure
change as we go up in the air?
Yes. Atmospheric pressure
decreases
3. Why don’t we feel the
enormous atmospheric pressure around us?
Because the pressure is equal
in all directions
4. What do you mean by absolute
temperature?
It is the temperature
measured on Kelvin scale
5. Is it possible to attain
absolute zero temperature in practice?
It is unattainable.
6. Mention three important thermometric
scales.
Celcius, Kelvin and
Fahrenheit scales.
7. Define atmospheric pressure.
Atmospheric pressure is defined
as the force per unit area due to the column of air of infinite height.
8. What is the effect of
temperature of air on the atmospheric pressure?
Atmospheric pressure
decreases with increase in temperature
9. What is the value of normal
atmospheric pressure?
1.013 x 105 Nm-2
= 105 Nm-2
10. State the unit of
pressure in S.I.
Ans: Nm-2 or
Pascal
11. What is one atmosphere?
Ans: It is the pressure
exerted by a column of 76 cm of mercury at 0 °C.
P = hdg = 0.76 x 13.6 x 103 x
9.8 = 1.013 x 105 Nm-2
12. Why should the air
enclosed in the bulb be dry?
Ans: The presence of water
vapour alters the reading
13. State Charles law
Ans: The volume of a given
mass of gas varies directly as its temperature in Kelvin scale when pressure is
kept constant. The pressure of a given mass of gas varies directly as its
temperature when volume is kept constant ie, V ∝ T and P ∝ T
14. State Boyle’s law.
At constant temperature, the
pressure of a given mass of gas is inversely proportional to its volume.
ie, P
∝
1/V, PV = a constant
15. Why do you use a
capillary tube to connect the bulb to the reservoir?
Ans: To ensure that most of
the air enclosed is at the constant temperature of the bath
16. What is the boiling
point of pure water at normal pressure in Kelvin scale?
Ans: 273 K
17. How do you define
pressure coefficient of a gas?
Ans: It is defined as the
ratio of the increase in pressure of the gas at constant volume per degree rise
of temperature to its pressure at 0 °C
18. Is the pressure
coefficient the same for all gases? If so what is its value?
Ans: Its value is same for
all gases and is equal to 1/273
19. Aim of the Jolly's Bulb
Apparatus Experiment?
Ans: To study the relation
between pressure and temperature of a sample of air at constant volume
20. Apparatus of the Jolly's
Bulb Apparatus Experiment?
Ans: Jolly's bulb apparatus,
water bath, thermometer, etc. The Jolly's bulb apparatus consists of a
spherical glass bulb A connected to a narrow capillary tube bent twice at right
angles. There is a fixed mark M made on this tube as shown in the figure. The
free end of the tube is connected to a reservoir R of mercury by means of thick
rubber tubing. The reservoir can be raised or lowered and can be fixed in any
position. The readings of the mercury levels may be noted on a scale S.
21. Theory of the Jolly's
Bulb Apparatus Experiment?
Ans: For a given mass of gas
(air) at constant volume, the pressure P is directly proportional to its
absolute temperature T.
i.e., P ∝ T or (P/ T) = a constant