Let A and B be two sets containing 2 elements and 4 elements respectively. The number of subsets of AB having 3 or more elements is :
211
256
220
219
n(A) = 4, n(B) = 2
Number of sbsets having atlest 3 elements
Option 1)
211
Incorrect
Option 2)
256
Incorrect
Option 3)
220
Incorrect
Option 4)
219
Correct
The length of a focal chord of the parabola y^{2} = 4ax at a distance b from the vertex is C. Then
2a^{2} = bc
a^{3} = b^{2}c
ac = b^{2}
b^{2}c = 4a^{3}
The inverse of the function is
None of these
Four identical electrical lamps are labelled 1.5V, 0.5A which describes the condition necessary for them to operate at normal brightness. A 12V battery of negligible internal resistance is connected to lamps as shown, then
The value of R for normal brightness of each lamp is
The value of R for normal brightness of each lamp is
Total power dissipated in circuit when all lamps are normally bright is 24W
Power dissipated in R is 21W when all lamps are normally bright
When the rms voltages V_{L}, V_{C} and V_{R} are measured respectively across the inductor L, the capacitor C and the resistor R in a series LCR circuit connected to an AC source, it is found that the ratio V_{L} : V_{C} : V_{R }= 1 : 2 : 3. If the rms voltage of the AC source is 100 V, then V_{R} is close to :
50 V
70 V
90 V
100 V
The radius of the circle passing through the points (1,2) (5,2)and (5,-2) is
The radius of the circle passing through the points (1,2),(5,2) and (5,-2) is
As we learnt in
Equation of a circle -
- wherein
Circle with centre and radius .
On substituting the value of (x, y) as (1, 2), we get
....................(1)
On substituting the value of (x, y) as (5, 2), we get
.........................(2)
On substituting the value of (x, y) as (5, -2), we get
.......................(3)
On subtracting Eq. (1) - (2), we get
h = 3
On subtacting Eq. (2) - Eq. (3), we get
k = 0
On
Option 1)
Incorrect
Option 2)
Incorrect
Option 3)
Incorrect
Option 4)
Correct
Which one of the following complexes shows optical isomerism ?
[Co(NH_{3})_{3}Cl_{3}]
cis[Co(en)_{2}Cl_{2}]Cl
trans[Co(en)_{2}Cl_{2}]Cl
[Co(NH_{3})_{4}Cl_{2}]Cl
(en=ethylenediamine)
3-Methyl-pent-2-ene on reaction with HBr in presence of peroxide forms an addition product. The number of possible stereoisomers for the product is :
Two
Four
Six
Zero
An organic compound A upon reacting with NH_{3 }gives B .On heating ,B gives C .C in presence of KOH reacts With Br_{2} to give CH_{3}CH_{2}NH_{2}. A is :
The final product formed when Methyl amine is treated with NaNO_{2} and HCl is
Diazomethane
Methylalcohol
Methylcyanide
Nitromethane
When the concentration of alkyl halide is tripled and concentration of OH^{-} is reduced to half, the rate of S_{N2} reaction increased by
3 times
1.5 times
2 times
6 times
The formula of Prussian Blue is
None of these
O - Chlorotoluene can undergo
(a) electrophillic aromatic substitution
(b) nucleophilic aromatic substitution
(c) nucleophilic aliphatic substitution
(d) free radical substitution
Only (a)
(a) and (d) only
(a), (b) and (d)
All of these
The structure of the major product formed in the given reaction is
Which of the following compounds can exist both as a pair of enantiomers and a trans pair of enantiomers?
Which reagent will you use for the following reaction?
CH_{3} CH_{2} CH_{2} CH_{3} CH_{3} CH_{2} CH_{2} CH_{2} Cl + CH_{3} CH_{2} CH Cl CH_{3}
Cl_{2} / UV light
NaCl + H_{2}SO_{4}
Cl_{2} gas in dark
Cl_{2} gas in the presence of iron in dark
Ethylidene Chloride on treatment with aq. KOH gives
Acetaldehyde
Ethylene Glycol
Acetone
Ethanol
Alkyl flourides are synthesised by heating an alkyl chloride / bromide in presence of which of the following?
(a) CaF_{2}
(b) COF_{2}
(c) Hg_{2}F_{2}
(d) NaF
(a) and (c)
(b) and (c)
(a) and (d)
(d) and (b)