List of practice Questions

The torque of force $ \vec{F}=(2\hat{i}-3\hat{j}+4\hat{k}) $ newton acting at a point $ \vec{r}=(3\hat{i}+2\hat{j}+3\hat{k}) $ metre about origin is:
$300 \,J$ of work is done in sliding a $2 \,kg$ block up an inclined plane of height $10\,m$. The work done against friction is (Take $ g=10\,m/{{s}^{2}} $ )
A particle is moving under the influence of a force which is fixed in magnitude and acting at an angle $ \theta $ in the direction of motion. The path described by the particle is:
A projectile is fired at $ 30{}^\circ $ with momentum $p$. Neglecting friction, tine change in kinetic energy, when it returns back to the ground, will be:
If a car at rest accelerates uniformly and attains a speed of $72 \,km/hr$ in $10 \,s$, then it covers a distance of:
Suppose refractive index $ \mu $ is given as $ \mu =A+B/{{\lambda }^{2}}, $ where $A$ and $B$ are constants and $X$ is wavelength then the dimensions of $B$ are same as that of:
A ball of mass $0.25 \,kg$ attached to the ends of a string of length $1.96 \,m$ is rotating in a horizontal circle. The string will break, if tension is more than $25\, N$. What is the maximum velocity with which the ball can be rotated?
If an iron ball and a wooden ball of the same radius are released from a height $ h $ in vacuum, then time taken by both of them, to reach the ground will be:
In uniform circular motion, the factor that remains constant is:
A common example of $\beta^{-}$decay is $15 P^{32} \rightarrow 16 S^{32}+x+y$ Then $x$ and $y$ stands for
A hot body at temperature $T$ losses heat to the surrounding temperature $T_{S}$ by radiation. If the difference in temperature is small then, the rate of loss of heat by the hot body is proportional to
Which one of the following statement is correct in the case of light emitting diodes?
A $0.5\, kg$ ball moves in a circle of radius $0.4\, m$ at a velocity of $4\, m / s$. The centripetal force on the ball is
A double convex lens $(\mu=3 / 2$ ) of focal length $20\, cm$ is totally immersed in water $(\mu=4 / 3)$. Its focal length now will be
An artificial satellite revolves around the earth in a circular orbit with a speed $ v $ . If m is the mass of the satellite, its total energy is
Under which of the following conditions is the law $ pV=RT $ obeyed most closely by a real gas?
For Balmer series that lies in the visible region, the shortest wavelength corresponds to quantum number
The hubble constant has the dimensions of
When a triode is used as an amplifier the phase difference between the input signal voltage and output is
In Youngs experiment, the wavelength of red light is $7800\, ?$ and that of blue light is $5200\, ?$. The value of n for which $ (n+1)th $ blue band coincides with nth red band is
The energy of an electron in excited hydrogen atom is $ -3.4\,eV $ . Then according to Bohrs theory, the angular momentum of the electron is
A ball of mass $0.5\, kg$ moving with a velocity of $2 \,ms ^{-1}$ strikes a wall normally and bounces back with the same speed. If the time of contact between the ball and wall is $10^{-3} s$, the average force exerted by the wall on the ball is
A research satellite of mass $200\, kg$ circle the earth in an orbit of average radius $ \frac{3R}{2}, $ where is the radius of the earth. Assuming the gravitational pull on a mass of $1\, kg$ on the earths surface to. be $10\, N$, the pull on the satellite will be
A telescope has an objective of focal length $50\, cm$ and an eye-piece of focal length $5\, cm$. The least distance of distinct vision is $25\, cm$. The telescope is focussed for distinct vision on a scale $200\, cm$ away. The separation between the objective and the eye-piece is
Consider the spectral line resulting from the transition from $ n=2 $ to $ n=1, $ in atoms and ions given below. The shortest wavelength is produced by