Calculate the stress developed inside a tooth cavity filled with copper when hot tea at temperature of 57o C is drunk. You can take body (tooth) temperature to be 37o C and α = 1.7× 10-5 /o C, bulk modulus for copper = 140 × 10 9 N/m2.
Coefficient of linear expansion, α = 1.7× 10-5 /°C
Therefore, Coefficient of volumetric expansion(𝛾)
𝛾 = 3α = 1.7× 10-5 /°C = 5.1× 10-5 /°C
Bulk modulus, B= 140 × 10 9 N/m2.
Body temperature, T1 = 37°C
Temperature of tea, T2 = 57 °C
Temperature difference, ΔT = 57 - 37 = 20 °C
Atmospheric pressure is 105 N/m2.
So, the stress is about 103 times atmospheric pressure.
Rate this question :
Calculate the stress developed inside a tooth cavity filled with copper when hot tea at temperature of 57o C is drunk. You can take body (tooth) temperature to be 37o C and α = 1.7× 10-5 /o C, bulk modulus for copper = 140 × 10 9 N/m2.Physics - Exemplar
We would like to prepare a scale whose length does not change with temperature. It is proposed to prepare a unit scale of this type whose length remains, say 10 cm. We can use a bimetallic strip made of brass and iron each of different length whose length (both components) would change in such a way that difference between their lengths remain constant. If αiron 1.2 X 10-5/ K and αbrass 1.8 X 10-5 /K , what should we take as length of each strip?Physics - Exemplar
A student records the initial length l, change in temperature ∆T and change in length ∆l of a rod as follows:
If the first observation is correct, what can you say about observations 2, 3 and 4.
Physics - Exemplar
A rail track made of steel having length 10 m is clamped on a railway line at its two ends (Fig 11.3). On a summer day due to rise in temperature by 20° C, it is deformed as shown in figure. Find x (displacement of the center) if αsteel = 1.2× 10-5 /°C.
Physics - Exemplar
We would like to make a vessel whose volume does not change with temperature (take a hint from the problem above). We can use brass and iron (βvbrass = 6 × 10-5/K and βviron = 3.55 ×10-5 / K) to create a volume of 100 cc. How do you think you can achieve this?Physics - Exemplar
As the temperature is increased, the time period of a pendulumPhysics - Exemplar
A thin rod having length L0 at 0° C and coefficient of linear expansion α has its two ends maintained at temperatures θ1 and θ2, respectively. Find its new length.Physics - Exemplar
A uniform metallic rod rotates about its perpendicular bisector with constant angular speed. If it is heated uniformly to raise its temperature slightlyPhysics - Exemplar
Answer the following questions based on the P-T phase diagram of carbon dioxide:
(a) At what temperature and pressure can the solid, liquid and vapour phases of CO2 co-exist in equilibrium?
(b) What is the effect of decrease of pressure on the fusion and boiling point of
(c) What are the critical temperature and pressure for CO2? What is their significance?
(d) Is CO2 solid, liquid or gas at (a) –70 °C under 1 atm, (b) –60 °C under 10 atm, (c) 15 °C under 56 atm?NCERT - Physics Part-II
A brass rod of length 50 cm and diameter 3.0 mm is joined to a steel rod of the same length and diameter. What is the change in length of the combined rod at 250 °C, if the original lengths are at 40.0 °C? Is there a ‘thermal stress’ developed at the junction? The ends of the rod are free to expand (Co-efficient of linear expansion of brass = 2.0 × 10–5 K–1, steel = 1.2 × 10–5 K–1).NCERT - Physics Part-II