New Concepts/Shortcuts 20

Question 1

what should be the first step for functions with graph or point of discontinuous such questions if there is the greatest integer function in it

Answer 1

break the functions with 1 integer gap so a

Question 2

what to do if we have to find the number o f non differentiable points

Answer 2

find the shak vaale points and break the functions range wise

Question 3

graph of {x}

Answer 3

Question 4

Answer 4

1/2

Question 5

why do we not need a continuous source of input in LC oscillators?

Answer 5

because we can send a little of output only again in the input oscillator

Question 6

how are the two inductors s mutually coiled

Answer 6

they are coiled by wounding on the RHS long rod and hence are mutually coupled and have the same flux

Question 7

why does the current don’t decay in LC oscillations

Answer 7

because the output is also sent in input which prevents it from decaying

Question 8

what changes if two inductors are mutually coupled

Answer 8

there is a pi phase change between the two oscillators

Question 9

why does the pi phase change isnt noticed n the final output of the LC oscillation circuit

Answer 9

because when the pi phase change happens due to the mutually coupled coiled
there is again a pi phase change due to the change in current from Ib to Ic and hence its gain back to 2pi or 0

Question 10

whats a tuned/tank circuit in LC oscillation diagram

Answer 10

Question 10

for a transistor to act as a switch it should operate in_____-

Answer 10

saturated and cut-off state

Question 11

whats positive feedback and negative feedback

Answer 11

the return of part of an output signal to the input, which is in phase with it, so that the amplifier gain is increased and often the output is distorted is called positive feedback

the return of part of an output signal to the input, which is out of phase with it, so that amplifier gain is reduced and the output is improved called negative feedback

Question 12

when does the transistor as a switch produce output and between what range is it decreasing and is constant

Answer 12

Question 13

whats half deflection method for galvanometer with 2 galvanometers given

Answer 13

it’s simple that we get half the deflection as compared to the earlier one that is half the Ig and similar if we have 1/3 deflection or 1/n deflection

Question 14

What’s the trick for these kinda questions?

Answer 14

Question 15

whats a shortcut for finding the number of isomers for alkyl halides

Answer 15

see how many different kinds of H are present in the compound! that would be the number of isomers

Question 15

whats a shortcut for finding the number of isomers for alkyl halides

Answer 15

see how many different kinds of H are present in the compound! that would be the number of isomers

Question 16

what does work does silica gel and calcium chloride with water vapour

Answer 16

Water vapours are absorbed by anhydrous calcium chloride but adsorbed by silica gel.

Question 17

how are gasses accumulated on the surface of a solid

Answer 17

If accumulation of gas on the surface of a solid occurs on account of weak van der Waals’ forces,

Question 18

chemisorption required high/low energy of activation

Answer 18

Chemisorption involves high energy of activation

Question 19

how is the amount of gas adsorbed depend on critical temperature?

Answer 19

easily liquefiable gases (i.e., with higher critical temperatures) are readily adsorbed as van der Waals’ forces are stronger near the critical temperatures. Thus, 1g of activated charcoal adsorbs more sulphur dioxide (critical temperature 630K), than methane (critical temperature 190K) which is still more than 4.5 mL of dihydrogen (critical temperature 33K)

Question 20

dependence of physical adsorption with temperature

Answer 20

Since the adsorption process is exothermic, the physical adsorption occurs readily at low temperature and decreases with increasing temperature

Question 21

the Freundlich isotherm constant has values between

Answer 21

0 and 1

Question 22

when is the adsorption independent of pressure?

Answer 22

when 1/n = 0
x/m= constant

and hence its constant

Question 23

when does the adsorption varies directly with pressure

Answer 23

when 1/n=1

x/m=constant

hence it caries directly

Question 24

what hapens whe litmus solution is shaken with charcoal

Answer 24

it bexomes colourless

Question 25

color of precipitate of Mg(OH)2 when precipitated in presence of magneson reagent

Answer 25

The precipitate of Mg(OH)2 attains blue colour when precipitated in presence of magneson reagent.

Question 26

what can be used to control humidity and remove moisture?

Answer 26

silica and aluminium gels

Question 27

how are inert gases separated?

Answer 27

Due to the difference in the degree of adsorption of gases by charcoal, a mixture of noble gases can be separated by adsorption on coconut charcoal at different temperatures

Question 28

what are adsorption indicators?

Answer 28

Surfaces of certain precipitates such as silver halides have the property of adsorbing some dyes like eosin, fluorescein, etc. and thereby producing a characteristic colour at the end point

Question 29

when does the decomposition of KClO3 occur?

and how is it reduced?

Answer 29

in a range of 653-873 K

when a little manganese dioxide is added, the decomposition takes place at a considerably lower temperature range, i.e., 473-633K, and also at a much-accelerated rate.

Question 30

What’s Ostwald’s process? and what’s the catalyst used in it?

Answer 30

catalyst= Pt

Question 31

whats homogenous catalysis

Answer 31

When the reactants and the catalyst are in the same phase (i.e., liquid or gas), the process is said to be homogeneous catalysis

Question 32

what will be the answer and why?

Answer 32

false

because the x(2R) is a significant value which will not result in an expression of force being directly proportional to the displacement! hence it is false

Question 33

silicone is what type of polymer?

Answer 33

condensation polymer of dialkyl silanediol

Question 34

which salts give green flame with blue center?

Answer 34

cupric salts

Question 35

the relation between time taken by a ball to free fall! fall with a velocity upwards! fall with the same velocity downwards

Answer 35

Question 36

formula for time taken for an object to free fall with 0 initial velocities in any acceleration

Answer 36

Question 37

the trick for a free falling object distance after 1-1seconds

Answer 37

Question 38

relation between Range and max heights reached by projectile projected with same velocity but different angle with the horizontal

Answer 38