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High School/JEE/NEET/IPhO Physics | 17-19 Yrs

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  1.  
  2. How can we write "w1 = w. (1 - Pl/Pm) " ? Is this the formula for apparent weight of substance in liquid?
    1 years ago by Shivam Kumar

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  3.  
  4. ADVANCED SUMS WHERE I CAN GET FOR OLYMPIAD
    1 years ago by abi sathwik

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  5.  
  6. plz add options to adjust speed of video
    2 years ago by Shivam Ranjan

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  7.  
  8. A spherical shell is heated. The volume changes according to the equation Vt= Vo (1 gamma theta).Does the volume refer to the volume enclosed by the shell or the volume of the material making up the shell? If answer is volume of material then why not the enclosed volume as sir has explained in the expansion of cavity. please explain !
    2 years ago by MD DANISH ZUNNOON

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  9.  
  10. Sir, I have a doubt... Does the alpha, beta, gamma also depend on atomic/molecular weight of an object... If so, then how? Sir, please clarify my doubt...
    3 years ago by Jaideep Rankawat

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  11.  
  12. are these lectures enough for NSEA/INAO?
    3 years ago by Jaideep Rankawat

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  13.  
  14. Sir, is thermal agitation = random oscillation motion
    3 years ago by

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  15.  
  16. sir please include the sys. of 2x speed
    3 years ago by Nitin

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  17.  
  18. Sir why did you take time lost or gained by clock per second as delta t = 1/2 alpha deltaT. but the formula was delta t/t = 1/2 alpha delta T
    3 years ago by Ayan Borchetia

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  19.  
  20. sir I am sai Shankar neet repeater sir in this topic there is no mentioning of expansion of liquids and expansion of gases will u upload
    3 years ago by shankar prasad

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  21.  
  22. Sir how can we use l=lo(1 alpha×T) for rod since its elongation is also influenced by other one of different material
    3 years ago by santhosh reddy

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  23.  
  24. sir why didnt u use the formula 1+gamaT
    3 years ago by Vishwas Sharma

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  25.  
  26. When a hollow spherical shell is heated then in the equation of v= vo( 1 gamma ?T) , v refers to the volume of material of shell or the volume enclosed by shell ?
    3 years ago by MD DANISH ZUNNOON

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  27.  
  28. So sir, can we conclude this module with this statement that a compensated pendulum is a pendulum where the center of mass of the entire system is independent of temperature?
    4 years ago by Eklavya Goyal

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  29.  
  30. So sir, can we conclude this module with this statement that a compensated pendulum is a pendulum where the center of mass of the entire system is independent of temperature?
    4 years ago by Eklavya Goyal

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  31.  
  32. can i download these videos
    4 years ago by Aryan OFFICIAL

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  33.  
  34. can we get these videos downloaded and see when ever we want
    4 years ago by Revu Supriya
    Ans 1 ->
    yes download from youtube
    4 years ago by Daily whatsapp status

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  35.  
  36. I love your book series and your lectures but due to lack of time I can only see your concept videos .please kindly publish a book with all advance illustrations as you did in your lectures.
    4 years ago by editor jst

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  37.  
  38. If sag is produced wont there be a tension in the wire?
    5 years ago by Kirtan Patel

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  39.  
  40. as you said alpha depends on original length hence should be diff. for l and b as they are diff.
    5 years ago by Hardik Jadwani

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  41.  
  42. Do we need knowledge of mechanics before studying thermodynamics?
    5 years ago by Malicious 84

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  43.  
  44. Thanks a lot ashish arora sir Are you great teacher and explanation sir ??????????
    5 years ago by Aditya Pathak

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  45.  
  46. Sir ap example discuss krne wale the.. Lekin video ni ha.
    6 years ago by Zakir Hussain

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  47.  
  48. Sir for getting density at 35 degree why to divide the density by 1 ¥t why not multiply it because generally in case of volume we multiply initial by 1 ¥t? ??????
    6 years ago by Tanaya sunil Shiknis
    Ans 1 ->
    same problem......
    5 years ago by vanshika deval
    Ans 2 ->
    Got it......watch the 3 Module of this series
    5 years ago by vanshika deval

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  49.  
  50. Why are we considering only volume in the case of cavity,but not area?
    6 years ago by HARSHA DARBHASAYANAM

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  51.  
  52. thanku sir for these videos which are improving my interest and marks in physics also i have a doubt in this video please please please reply sir ; if the pendulum is 5 sec fast then temp is 10 sec slow so the eqn becomes 5 = 1/2.alpha.(t not-15).86400 similarly in 2nd eqn it becomes -10=1/2.alpha.(tnot 300).86400 as the time decreases temp increases is this true please please reply sir
    6 years ago by teja

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  53.  
  54. Sir, from where did you get w1=w0(1-PL/Pm)?
    6 years ago by Aarohi Khodkumbhe
    Ans 1 ->
    fluids( apparent weight of solid in liquid)
    6 years ago by vinayak agrawal

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  55.  
  56. how to learn such big formula . or is it necessary to learn this formula . if not than what thing we should learn from this wieght thermometre for jee advance.
    6 years ago by raghav dhamani

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  57.  
  58. the resistance of a resistance thermometer has values 2.71 and 3.7 ohm at 10 and 100 degree celcius . the temp at which the rsis is 3.26 ohm is ? sir ,i get the answer as 60 degree , but at the back , 50 degree is given !? in the last step i got, 55/1.1 = T-10 ..T=60 celcius ....
    7 years ago by nemo tyson

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  59.  
  60. Sir if we assume that the solid considered is a metal ex.iron so we know that according to electron sea model the two Fe+2 atoms cannot collide as for collision of like charges we require infinite energy.so sir do they really collide with each other?
    7 years ago by Pragyan vashishth

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  61.  
  62. Sir I did not understand where did the numerator came from?
    7 years ago by Abhishek yadav

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  63.  
  64. How to find actual length of a rod when both rod and scale measuring rod expand?
    7 years ago by Pushpa Latha
    Ans 1 ->
    This is already explained in advance illustrations, you need to watch these videos...
    7 years ago by Physics Galaxy

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  65.  
  66. sir how did you wrote weight W2 at temperature T2??
    7 years ago by Dhruv Narayan Gupta

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  67.  
  68. sir why you took 15-t0 in numerator and 30-t0 in denominator???????????????
    7 years ago by Mohammad Abbas

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  69.  
  70. Lets say you have 3 rods AB BC and CA of equal length forming a equilaterial triangle. The distance between the vertices C and the mid point of side AB is always constant even if the temp changes. AB rod has coeeficeient of linear exp as alpha1 and BC and CA rods both have alpha 2. We need to find relation between alpha 1 and alpha 2. Sir the answer is alpha 1= 4 alpha 2. But how? sir plz say the procedure.
    7 years ago by Krishna Behera
    Ans 1 ->
    Sir please answer the above question I am very much curious about it?
    7 years ago by Abhishek yadav

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  71.  
  72. sir how to solve this question:
    7 years ago by Krishna Behera

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  73.  
  74. instead of saying temperature you have said tension please correct
    8 years ago by Faizan Ali Saiyed

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  75.  
  76. when we supply heat to a substance its volume increase. Doesnt it mean that the pressure decreases?
    8 years ago by madhumitha
    Ans 1 ->
    here temp is not constant to apply pv=const here temp is incresing
    7 years ago by lingagiri deva datta charan

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  77.  
  78. 8 years ago by AADAR JAIN

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  79.  
  80. sir is it necessary to watch KTG and Laws of thermo to understand heat transfer ??
    8 years ago by Prakhar Raghuvanshi
    Ans 1 ->
    not at all
    7 years ago by Ayush Sharma

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  81.  
  82. Sir if liquid is in a tube which do not expand with temp then its gamma can be taken as its alpha ?
    8 years ago by Simran
    Ans 1 ->
    Yes if cross sectional area of tube is constant then we can use cubical coefficient as linear expansion coefficent for length of liquid in the tube...
    8 years ago by Physics Galaxy

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  83.  
  84. sir if we join the centres of cavity and the solid is the equation valid? The two points are bounded by diff media.
    8 years ago by Aditi Gupta
    Ans 1 ->
    Yes; every linear dimension of an object changes in the same way when the temperature changes.
    8 years ago by Aanandita Dhawan

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  85.  
  86. Good Sir
    8 years ago by Prabh Prabh Simran
    Ans 1 ->
    thankyou
    8 years ago by Faizan Ali Saiyed

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  87.  
  88. how much time i should take to finish my heat and thermodynamics chapter???
    8 years ago by BALAJI MJ

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  89.  
  90. sir i dint understant how u used D/1+a(deltaT) Please clear this doubt sir i am facing same problem in every numerical
    8 years ago by Vaishnavi Kulkarni
    Ans 1 ->
    if a liquid expands or contracts its mass remains conserved. so D1.V1=D2.V2 and V2=V1(1+a0t)
    8 years ago by Aditi Gupta

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  91.  
  92. sir if aluminium expands more how do we know it is concave towards the copper strip?
    8 years ago by Vaishnavi Kulkarni
    Ans 1 ->
    since alpha(Al) is greater than alpha(Cu) and change in length is directly proportional to alpha
    8 years ago by Aditi Gupta

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  93.  
  94. i failed to understand m=v(Rl-Rc)T.D0/(1+RlT) i understood the numerator sir but in denominator what exactly did you do..?
    8 years ago by Vaishnavi Kulkarni
    Ans 1 ->
    If we take the relation of volume expansion and replace volumes by mass/density we get the final density to be (density initial)/ (1+Â¥?T)
    7 years ago by Abhishek yadav

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  95.  
  96. sir how do you calculate numerical calculation so fast??
    8 years ago by Mrigank Jain
    Ans 1 ->
    You need practice for it.
    6 years ago by Aarohi Khodkumbhe

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  97.  
  98. If the volume of gas is some constant.then ru assuming it as 0 sir??
    8 years ago by sachin

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  99.  
  100. a horizontal cylinder of cross sectional area A is fitted with two pistons and connected by in extensible wire. Initial temperature T , pressure P which equals the atmospheric pressure. Find the tension in the wire if temperature is raised to 3T. PLS ANSWER FAST.
    9 years ago by sezal
    Ans 1 ->
    Here as volume between the pistons is constant on increasing temperature to 3 times... pressure will also become 3 times so final tension in wire can be calculated by equilibrium of piston which is equal to 3PA...
    9 years ago by Physics Galaxy

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  101.  
  102. when we increase the temp. of the rod ...with linear expansion ,,area will also expand due to which stress also changes gradually so how can we take constant area and therefore const. stress
    9 years ago by Ritik Shrivastava
    Ans 1 ->
    As thermal expansion coefficient is a very small so for small temperature variations in the range where we take alpha constant we neglect the change in area as such a small change in area doesn't affect the stress by significant value...
    9 years ago by Physics Galaxy
    Ans 2 ->
    But if that's the case.. That alpha is small..then we should neglect linear expansion too N after all length varies with alpha n area with 2(alpha).. Please answer..
    9 years ago by Aanandita Dhawan
    Ans 3 ->
    My friends here we are talking about the cross sectional area and not the surface area. since expansion depends on initial length and since the radius is very small in comparison to the length of the rod therefore the increase in cross-sectional area can be safely assumed to be negligible.
    8 years ago by Mrigank Jain
    Ans 4 ->
    Right! Thanks.
    8 years ago by Aanandita Dhawan

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  103.  
  104. what is thermodynamics ?
    9 years ago by aditya waghmare
    Ans 1 ->
    Thermodynamics is a branch of physics concerned with heat and temperature and their relation to energy and work.
    9 years ago by Ninad Akolekar

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  105.  
  106. What about a digital thermometer?
    9 years ago by Ninad Akolekar
    Ans 1 ->
    A digital thermometer is calibrated for its temperature varying property and shows the reading on digital display...
    9 years ago by Physics Galaxy
    Ans 2 ->
    temeprature being a function of induced emf due to changes in heat supplied or recieved ..
    8 years ago by yashwanth

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  107.  
  108. If temperature is a 'measure of energy...' then its dimensions should be same as that of Energy??
    9 years ago by Ninad Akolekar
    Ans 1 ->
    No... as brightness of light is also a measure of power consumption of a bulb but its dimensions are not as that of power or energy... its defined as illuminance... similarly temperature gives an idea about the thermal energy content of body not analytical measurement...
    9 years ago by Physics Galaxy

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  109.  
  110. sir, Is there any other way of finding tension in clamped wire .....instead of using young's modulus? unable to understand concepts of stress nd strain...
    9 years ago by TISTA LATHER
    Ans 1 ->
    To understand stress and strain...you need to first go through the concepts of Elasticity... first view all videos of Elasticity in sequence then try to understand it... it will help you...
    9 years ago by Physics Galaxy

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  111.  
  112. cofficient of thermal expansion
    10 years ago by devendra sain
    Ans 1 ->
    change in dimension per unit dimension per degree raise in temparature
    8 years ago by yashwanth

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  113.  
  114. 2 identical hollow metal spheres, one is empty (vacuum) and other is filled with air. Both are heated such that temp. of each rise by same amount. One in which air is filled will expand more.WHY??
    10 years ago by Kshitiz agrawal
    Ans 1 ->
    Due to pressure of air and elasticity of sphere (bulk modulus) it will expand more...
    9 years ago by Physics Galaxy

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  115.  
  116. 45 gm of alcohol are needed to completely fill up a weight thermometer at 15 degree Celsius. Find.Find the weight of alcohol which will overflow when the weight thermometer is heated to 33 degree Celsius. (Given gamma a = 121 * 10 power -5 / degree Celsius.
    10 years ago by Dr.Upendra Singh
    Ans 1 ->
    0.9 g
    9 years ago by Aanandita Dhawan

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  117.  
  118. When a rod is heated but prevented from expanding the stress developed is independent of - a. Material of rod b.Rise in temperature c. Length of rod d. None of these Sir, please explain the reason for your answer....
    10 years ago by Dr.Upendra Singh
    Ans 1 ->
    c. For the explanation, pl watch the video http://physicsgalaxy.com/lectures/1/14/277/Force%20Between%20a%20Rod%20and%20Rigid%20Walls#5
    9 years ago by Physics Galaxy

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