List of top Physics Questions

Two bodies are projected simultaneously with the same velocity of 19.6 m/s from the top of a tower, one vertically upwards and the other vertically downwards As they reach the ground, the time gap is

Two resistors of resistances $ 200\,k\Omega $ and $ 1\,M\Omega $ respectively form a potential divider with outer junctions maintained at potentials of $ +3V $ and $ -15V $ . Then, the potential at the junction between the resistors is

In the circuit shown, the current through the $ 5\,\Omega $ resistor is

In a meter bridge experiment, resistances are connected as shown in figure. The balancing length $ l_1 $ is 55 cm. Now an unknown resistance x is connected in series with P and the new balancing length is found to be 75 cm . The value of x is

Two identical conductors maintained at different temperatures are given potential differences in the ratio 1 : 2. Then the ratio of their drift velocities is

On increasing the temperature of a conductor. its resistance increases because the

An ammeter, voltmeter and a resistor are connected in series to a cell and the readings are noted as $I$ and $V$ . If another resistor $R$ is connected in parallel with voltmeter, then

In a closed circuit, the current $ I $ (in ampere) at an instant of time $t$ (in second) is given by $ I=4-0.08t $ . The number of electrons flowing in $ 50\, s $ through the cross-section of the conductor is

In a potentiometer experiment, when three cells $A, B$ and $C$ are connected in series the balancing length is found to be $740\, cm$. If $A$ and $B$ are connected in series balancing length is $440\, cm$ and for $B$ and $C$ connected in series that is $540 \,cm$. Then the emf of $ {{E}_{A}},{{E}_{B}} $ and $ {{E}_{C}} $ are respectively (in volts)

In a potentiometer of wire length $l$, a cell of emf $V$ is balanced at a length $\frac{l}{3}$ from the positive end of the wire. For another cell of emf $1.5\,V$, the balancing length becomes

In the figure shown below, the terminal voltage across $ {{E}_{2}} $ is

Nichrome is used as electrical heating element because of its

When two resistances $ {{R}_{1}} $ and $ {{R}_{2}} $ are connected in series, they consume $ 12 \,W $ power. When they are connected in parallel, they consume $ 50\, W $ power. What the ratio of the powers of $ {{R}_{1}} $ and $ {{R}_{2}} $ ?

$1$ ampere current is equivalent to

$8$ identical cells, each of emf $E$ and internal resistance $r$, are connected in series. If polarity of two cells is reversed then the total internal resistance in the circuit will be

A 10 m long wire of resistance $ 20O $ is connected in series with a battery ofemf3V and a resistance of $ 10O $ The potential gradient along the wire in V /m is

At room temperature, copper has free electron density of $8.4 \, \times \, 10^{28} \, m^{- 3}$ . The electron drift velocity in a copper conductor of cross-sectional area $10^{- 6} \, m^{2}$ and carrying a current of $5.4 \, A$ , will be -

A $220\, volts$ and $100\, watt$ bulb is connected to a $110$ volt source. What is the power consumed by the bulb?

A battery, an open switch and a resistor are connected in series as shown in figure.

Consider the following three statements concerning the circuit. A voltmeter will read zero if it is connected across points (i) $P$ and $T$ (ii) $P$ and $Q$ (iii) $Q$ and $T$ Which one of the above is/are true ?

A battery has e.m.f. $4V$ and internal resistance $r$. When this battery is connected to an external resistance of $2\,\Omega $, a current of $1A$ flows in the circuit. How much current will flow if the terminals of the battery are connected directly

A battery of emf $15\, V$ and internal resistance of $4\,\Omega$ is connected to a resistor. If the current in the circuit is $2 \,A$ and the circuit is closed. Resistance of the resistor and terminal voltage of the battery will be

A car battery of e.m.f. $12 V$ and internal resistance $5 \times 10^{-2} \Omega$ receives a current of $60 A$ from an external source, then terminal potential difference of battery is :-

A current in a wire is given by the equation, $I = 2t^2 - 3t + 1$, the charge through cross section of wire in time interval $t = 3\, s$ to $t = 5\,s$ is

A heater coil is cut into two equal parts and only one part is used in the heater, the heat generated becomes

A piece of wire of resistance 4 ohm is bent through 180 at its mid point and the two halves are twisted together. Then the resistance is