List of practice Questions

In forward biased if the $ p-n $ junctions diode is forward biased, then width of potential barrier in $ p-n $ junction diode :
Fluoride pollution mainly affects
The correct order of stability of carbocations, is:
Acrilan is a hard, horny and a high melting material. Which of the following represents its structure ?
Hesss law states that
A gas can expand from 100 mL to 250 mL undera constant pressure of 2 atm. The work done by the gas is
Yellow light is used in single slit diffraction experiment with slit width 0.6 mm. If yellow light is replaced by X-ray then the pattern reveals
The phenomenon of rotation of plane polarised light is called
Pyruvic acid is a product of
July 11 is observed as
Ethyl isocyanide on hydrolysis in acidic medium generates
Several blocks of magnesium are fixed to the bottom of a ship to
When rain is accompanied by a thunderstorm, the collected rain water will have a pH value
Bottles containing $ {C6H5I}$ and $ {C6H5CH2I}$ lost their original labels. They were labelled A and B for testing. A and B were separately taken in test tubes and boiled with $ {NaOH }$ solution. The end solution in each tube was made acidic with dilute $ {HNO3}$ and then some $ {AgNO3}$ solution was added. Substance B gave a yellow precipitate. Which one of the following statements is true for this experiment ?
The atomic number of V, Cr, Mn and Fe are respectively 23, 24, 25 and 26.Which one of these may be expected to have the highest second ionisation enthalpy ?
According to the kinetic theory of gases, in an ideal gas, between two successive collisions, a gas molecule travels
For making good quality mirrors, plates of float glass are used. These are obtained by floating molten glass over a liquid metal which does not solidify before glass. The metal used can be
A particle performing uniform circular motion has angular momentum $L$. If its angular frequency is doubled and its kinetic energy halved, then the new angular momentum is
A particle covers $150\, m$ in $8^\text{th}$ second starting from rest, its acceleration is:
A neutron makes a head-on elastic collision with a stationary deuteron. The fractional energy loss of the neutron in the collision is
A marble block of mass $2 \,kg$ lying on ice when given a velocity of $6\, m/s$ is stopped by friction in $10\, s$. then the coefficient of friction is
A lead shot of $1\, mm$ diameter falls through a long column of glycerine. The variation of its velocity $v$ with distance covered is represented by
A horizontal force of $10\, N$ is necessary to just hold a block stationary against a wall. The coefficient of friction between the block and the wall is $0.2$. The weight of the block is
Quality depends on:
Two closed organ pipes $100\, cm $ and $101 \,cm$ long gives $16$ beats in $20 \,s$, when each pipe is sounded in its fundamental mode. Calculate the velocity of sound: