List of top Physics Questions

If linear density of a rod of length 3 m varies as $ \lambda =2+x, $ then the position of the centre of gravity of the rod is:
The dimensional formula for the gravitational constant is:
A particle is moving in a circle of radius R with constant speed v. If radius is doubled, then its centripetal force to keep the same speed gets:
When earth moves round the sun, the quantity which remains constant is:
A particle moves along Y-axis in such a way that its y-coordinate varies with time $t$ according to the relation $y = 3 +5t + 7t ^2$. The initial velocity and acceleration of the particle are respectively
$1$ kg body explodes into three fragments. The ratio of their masses is $1:1:3$. The fragments of same mass move perpendicular to each other with speeds $30$ m/s, while the heavier part remains in the initial direction. The speed of heavier part is:
Two rods of same material have same length and area. The heat $ \Delta Q $ flows through them for $12\, min$ when they are joint side by side. If now both the rods are joined in parallel, then the same amount of heat $ \Delta Q $ will flow in:
A machine which is 75% efficient, uses 12 J of energy in lifting 1 kg mass through a certain distance. The mass is then allowed to fall through the same distance. The velocity at the end of its fall 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 $Cu = 63$)
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 :
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:
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:
Calculate the amount of heat (in calories) required to convert $5\, g$ of ice at $0^{\circ}C$ to steam at $100^{\circ}C$ .
A ray falls on a prism $ABC.(AB = BC)$ and travels as shown in figure. The least value of refractive index of material of the prism, should be:
A body takes time $t$ to reach the bottom of an inclined plane of angle $ \theta $ with the horizontal. If the plane is made rough, time taken now is $2t$. The coefficient of friction of the rough surface is:
A body of mass $m$ is moving towards east and another body of equal mass is moving towards north. If after collision both stick together, their speed after collision would be:
A body of mass $1\, kg$ is moving in a vertical circular path of radius $1\, m$. The difference between the kinetic energies at its highest and lowest position is :