List of top Physics Questions

Time period of a simple pendulum of length $l$ is $T_{1}$, and time period of a uniform rod of the same length $l$ pivoted about one end and oscillating in a vertical plane is $T_{2}$. Amplitude of oscillation in both the cases is small. Then $T_{1}/T_{2}$ is
An insulator plate is passed between the plates of a capacitor. Then the displacement current
A hole is drilled in a copper sheer. The diameter of the hole is 4.24 cm at 27.0$^\circ$C . What is the change in the diameter of the hole when the sheet is heated to 227$^\circ$C ? Coeffecient of linear expansion of copper = $1.70 \times 10^{-5}\,K^{-1}$
A circuit consists of five identical conductors as shown in figure. The two similar conductors are added as indicated by the dotted lines. The ratio of resistances before and after addition will be
A hiker stands on the edge of a cliff $490\,m$ above the ground and throws a stone horizontally with a speed of $15\,ms^{-1}$. The time taken by the stone to reach the ground is
A heavy box having a mass of $300\, kg$ is pulled along the floor for $10\, m$. If the coefficient of sliding friction is $0.2$, kilocalories of heat produced is
A helium nucleus makes full rotation in a circle of radius 0.8 min 2 s. The value of'magnetic field B at the centre of the circle, will be $(\mu _0=$ permeability constant)
A heavy nucleus at rest breaks into two fragments which fly off with velocities in the ratio 3 : 1. The ratio of radii of the fragments is
A guitar string is $90\, cm$ long and has a fundamental frequency of $124\, Hz$. To produce a fundamental frequency of $186\, Hz$, the guitar should be pressed
A glass is full of water at $4^{\circ}\,C$, when it is (a) cooled (b) heated then, which one of the following is correct
A glass slab of thickness 4 cm contains the same numbers of waves as 5 cm of water when both are traversed by the same monochromatic ray of light. The refractive index of water is 4/3, what is that for glass ?
A girl standing on a stationary lift (open from above) throws a ball upwards with initial speed $50 \,m \,s^{-1}$. The time taken by the ball to return to her hands is (Take $g= 10 \,m \,s^{-2}$)
A girl press her physics text book against a rough vertical wall with her hand. The direction of the frictional force on the book exerted by the wall is
A giant refracting telescope at an observatory has an objective lens of focal length $15\, m$. If an eye piece of focal length $.0 \,cm$ is used, what is the angular magnification of the telescope?
A gas thermometer measures the temperature from the variation of pressure of a sample gas. If the pressure measured at the melting point of lead is 2.2 times the pressure measured at the triple point of water . Find the meiting point lead
A galvanometer of resistance 100 ohms is shunted so that only 1/11 of the main current flows through the galvanometer. The resistance of the shunt is
A galvanometer coil has a resistance of $15\, \Omega$ and the metre shows full scale deflection for a current of $4 \,mA$. To convert the meter into a voltmeter of range $0$ to $18\, V$, the required resistance is
$A$ galvanometer having a resistance of $50 \, \Omega$, gives a full scale deflection for a current of $0.05 \,A$. The length (in metres) of a resistance wire of area of cross section $3\times 10^{-2}\, cm^{2}$ that can be used to convert the galvanometer into an ammeter which can read a maximum of $5 \,A$ current is (Specific resistance of the wire $\rho=5\times10^{-7}\,\Omega\,m)$
A fully charged capacitor $C$ with initial charge $Q_0$ is connected to a coil of self inductance $L$ at $t = 0$. The time at which the energy is stored equally between the electric and the magnetic field is
A freely falling body takes 't' second to travel first $(1/x)^{th}$ distance. Then, time of descent is
A film of water is formed between two straight parallel wires each 0.1 m long and at a separation of $5\times 10^{-3}m$. calculate the work required to increase $1 \times 10^{-3}m$ distance between wires ( surface Tension of water = 0.072N/m )
A film of water is formed between two straight parallel wires of length 10cm each separated by 0.5 cm. If their separation is increased by 1 mm while still maintaining their parallelism how much work will have to be done ofwater (Surface tension of water $=(7.2 \times 10^{-2} \,N/m$ )
A fielder in a cricket match throws ball from the boundary line to the wicket keeper. The ball describes a parabolic path. Which of the following quantities remain constant during the motion in air? (Neglecting air resistance)
A fighter plane flying horizontally at an altitude of $1.5\,km$ with speed $720\,km\,h^{-1}$ passes directly overhead an anti-aircraft gun. At what angle from the vertical should the gun be fired for the shell with muzzle speed $600\,ms^{-1}$ to hit the plane. (Take $g = 10\,ms^{-2}$)
A faulty thermometer has $90.5^{\circ} \,C$ and $0.5^{\circ} \,C$ as upper and lower fixed points respectively. What is the correct temperature if this faulty thermometer reads $15.5^{\circ} C$