List of top Questions asked in DUET

Starch is converted to ethanol by fermentation. The sequence of enzymes used are

The volume of a cube in $ m^3 $ is equal to the surface area of the cube in $m^2$. The volume of the cube is

The certain amount of current when flowing in a properly set tangent galvanometer, produces a deflection of $45^{\circ} $ . The current be reduced by a factor of $ \sqrt{3} $ , the deflection would

On reduction with hydrogen, $3.6\, g$ of an oxide of metal left $3.2\, g$ of metal. If the vapour density of metal is $32$, the simplest formula of the oxide would be

Ionic compounds are formed most easily with:

A metal surface is exposed to solar radiations:

Number of unpaired electrons in $Mn^{4+}$ is :

When a man increases his speed by $2\, ms^{-1}$, the finds that his kinetic energy is doubled, the original speed of the man is

What is the drift velocity of electons, if the current flowing through a copper wire of $1\,mm$ diameter is $1.1\, A$ ? Assume that each atom of copper contributes on electron (Given, density of $Cu= 9 g \, cm^{-3}$ and atomic weight of $Cu = 63$)

Two plates (area = $S$) charged to $ +q_{1}$ and $ +q_{2}(q_{2} < q_{1})$ brought closer to form a capacitor of capacitance $C$. The potential difference across the plates is:

Magnification of a compound microscope is $30$. Focal length of eyepiece is $5\, cm$ and the image is formed at a distance of distinct vision $25\, cm$. The magnification of the objective lens is :

If percentage change in current through resistor is $1\%$, then the change in power through it would be :

Hailstone at $0^{\circ}C $ falls from a height of $1\, km$ on an insulating surface converting whole of its kinetic energy into heat. What part of it will melt? $ (g=10\,m/s^{2})$ (Latent heat of ice $ =3.34\times 10^{5}J/kg$)

Escape velocity from a planet is $ V_{e}$ . If its mass is increased to $8$ times and its radius is increased to $2$ times, then the new escape velocity would be:

Lattice energy of alkali metal chlorides follows the order :

The resistance of tungsten filament at $150^{\circ} C$ is $133 \Omega$ what will be its resistance at $500^{\circ} C$ ? The temperature coefficient of resistance of tungsten is $0.0045 /{ }^{\circ} C$.

On reduction with hydrogen, $3.6 \,g$ of an oxide of metal left $3.2 \,g $ of metal. If the vapour density of metal is $32$ , the simplest formula of the oxide would be :

The solubility product of $Ag _{2} CrO _{4}$ is $32 \times 10^{-12}$. What is the concentration of $CrO _{4}^{2-}$ ions in that solution (in $g$ ions $\left.L^{-1}\right)$ ?

The monomer of nylon-6 is/are :

The probability of electrons to be found in the conduction band of an intrinsic semiconductor at a finite temperature :

A string of length $ l $ fixed at one end carries a mass m at the other end. The string makes $ \frac{2}{\pi } $ rev/s around the horizontal axis through the fixed end as shown in the figure, the tension in string is :

For a transistor, in a common emitter arrangement, the alternating current gain $P$ is given by :

What is the value of linear velocity, if angular velocity is $3 \hat i - 4 \hat j + \hat k$ and distance from the centre is $5 \hat i - 6 \hat j + 6 \hat k$ ?

The angular momentum of a system of particles is not conserved :

Figure shows a body of mass m moving with a uniform speed $v$ along a circle of radius $r$. The change in velocity in going from $A$ to $B$ is: