Mehapatel

A buffer solution is one which resists changes in pH when small quantities of an acid or an alkali are added to it.
HClO4 and NaClO4 are not an acidic buffer because strong acid with its salt cannot form buffer solution.

After infecting the human body the HIV gains entry into the macrophages. Events that occur in the cells:i. The virus enters into macrophages where RNA genome of virus replicates to form viral DNA with the help of enzyme reverse transcriptase.ii. The viral DNA gets incorporated into host cells DNAand directs the infected cell to produce virus particles. iii. The macrophage continue to produce virus and in this way acts like a HIV factory.iv. The HIV enters into helper T-lymphocytos (TH ), replicates and produce progeny viruses. The progeny viruses released in the blood attacks other helper T-h

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The doctor laid the child upon a blanket and began the special method of respiration. He took two basins. Like some crazy juggler he plunged the child into the icy water. Then he hurried him into the other basin containing steaming water. After labouring in vain for 15 minutes a sense of defeat pressed on him.

G0 is the phase which undergoes differentiation. It is also known as quiscent phase.

घर्षण के लाभ
घर्षण के हानि
1. वस्तु की स्थिति को बनाए रखना: घर्षण किसी भी वस्तु की स्थिति तथा उसके आकार को स्थिर रखती है।
1. वस्तु में टूट तथा फूट होना-घर्षण के कारण वस्तु में हमेशा टूट तथा फूट होती रहती है, इसे बचाने के लिए हमें वस्तुओं, तेल या चिकनाई आदि का प्रयोग करना चाहिए।


2. गति में सहायता करना: घर्षण के कारण हम आराम से चल व दौड़ पाते है। धावक गति में तेजी लाने के लिए घर्षण को बढ़ाता है जैसे- स्पाइक्स (Spikes) का प्रयोग धावक द्वारा करना।
2. ऊर्जा का नुकसान: घर्षण हमारे कामो में बहुत सारी ऊर्जा को खत्म कर देता है।


3. पकड़ को मजबूत बनाना: घर्षण के कारण खिलाड़ी अपने हाथों से वस्

This law states thatIn case of TP:"If more and more units of a variable factor are employed with fixed factors, total product (TP) increases at diminishing rate and finally starts falling."In case of MP:"If quantities of a certain variable factor are increased while quantities of other factors are fixed, MP first increases, then may become constant and finally declines."Tabular and Diagrammatic presentation:


Land (Acre)
No. of labourers
TP (Quintal)
AP (Quintal)
MP  (Quintal)
 


1
0
0
0
-
 


1
1
2
2
2
Ist Phase


1
2
6
3
4


1
3
12
4
6


1
4
16

Metal oxide = M0.98O If ‘x’ ions of M are in +3 state, then 3x + (0.98 – x) × 2 = 2 x = 0.04 So the percentage of metal in +3 state would be

आर्थिक क्रियाओ को वर्गीकरण तीन क्षेत्रकों में वर्गीकृत किया गया है-
(i) प्राथमिक क्षेत्रक - प्राथमिक क्षेत्रक में कृषि, वानिकी, पशुपालन, मत्स्यपालन, मुर्गीपालन और खनन एवं उत्खनन शामिल हैं। 
(ii) द्वितीयक क्षेत्रक -द्वितीयक क्षेत्रक में विनिर्माण शामिल है। 
(iii) तृतीयक क्षेत्रक- तृतीयक क्षेत्रक में व्यापार, परिवहन, संचार, बैंकिंग, शिक्षा, स्वास्थ्य, बीमा, बैंकिंग आदि सेवाएं शामिल है। 
 

Given, a galvanometer coil.Resistance on the galvanometer, R = 12 ΩCurrent on galvanometer, Ig =3 mA = 3 x 10–3 AVoltage ,V = 18 VBy using formula,                      V = Ig(R+Rg)                     VIg = R+Rg  or,                               R = VIg-Rg     = 183×10-3-12R = 6 × 103-12 = 5988Ω

Paramagnetic character depend on the number of unpaired electron present in any complex. In [CoF6]3–, Co is having four unpaired electrons as F– does not cause pairing of electrons in d-orbitals, whereas in case of [Co(C2O4)3]3–, C2O4 causes pairing of unpaired electrons in d–orbitals and thus there is no unpaired electron, hence it is diamagnetic in nature.

The Young's double slit experiment belongs to a general class of "double path "experiments, in which a wave is split into two separate waves that later combine into a single wave.In water λ is reduced to λμ so λ' so λ' =λ16As ω=Dλd∝λ      ω'ω=λ'λ=λ16λ  or ω'=0.81.6=0.5mm