If a wire of resistance $20\,\Omega $ is covered with ice and a voltage of $210\, V$ is applied across the wire, then the rate of melting of ice is .................. $g/s$
Medium
Download our app for free and get startedPlay store
$H = \frac{{{V^2}}}{R} \times t = \frac{{{{(210)}^2}}}{{20}} \times 1 = mL$

 $\frac{{{{(210)}^2}}}{{20}} = m \times 80 \times 4.2$ $ \Rightarrow $ $m = 6.56\,\,g/s\,$

art

Download our app
and get started for free

Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*

Similar Questions

  • 1
    A cell of constant $e.m.f.$ first connected to a resistance ${R_1}$ and then connected to a resistance ${R_2}$. If power delivered in both cases is then the internal resistance of the cell is
    View Solution
  • 2
    The figure shows a circuit having eight resistances of $1 \Omega$ each, labelled $R_1$ to $R_8$, and two ideal batteries with voltages $\varepsilon_1=12 V$ and $\varepsilon_2=6 V$.

    Which of the following statement($s$) is(are) correct?

    $(A)$ The magnitude of current flowing through $R_1$ is $7.2 A$.

    $(B)$ The magnitude of current flowing through $R_2$ is $1.2 A$.

    $(C)$ The magnitude of current flowing through $R_3$ is $4.8 A$.

    $(D)$ The magnitude of current flowing through $R_5$ is $2.4 A$.

    View Solution
  • 3
    Four resistances of $100$ $\Omega$ each are connected in the form of square. Then, the effective resistance along the diagonal points is .............. $\Omega$
    View Solution
  • 4
    The resistivity $(\rho)$ of semiconductor varies with temperature. Which of the following curve represents the correct behaviour
    View Solution
  • 5
    A $220\, volt$ and $800\, watt$ electric kettle and three $220\, volt$ and $100\, watt$ bulbs are connected in parallel. On connecting this combination with $220\, volt$ electric supply, the total current will be ................ $ampere$
    View Solution
  • 6
    In a circuit shown in the figure, the capacitor $C$ is initially uncharged and the key $K$ is open. In this condition, a current of $1 \mathrm{~A}$ flows through the $1 \Omega$ resistor. The key is closed at time $t=t_0$. Which of the following statement($s$) is(are) correct?

    [Given: $\mathrm{e}^{-1}=0.36$ ]

    ($A$) The value of the resistance $R$ is $3 \Omega$.

    ($B$) For $t$

    ($C$) At $t=t_0+7.2 \mu \mathrm{s}$, the current in the capacitor is $0.6 \mathrm{~A}$.

    ($D$) For $t \rightarrow \infty$, the charge on the capacitor is $12 \mu C$.

    View Solution
  • 7
    A current i passes through a wire of length $l$, radius of cross-section $r$ and resistivity $\rho$. The rate of heat generation is
    View Solution
  • 8
    An electric current is passed through a circuit containing two wires of the same material, connected in parallel. If the lengths and radii of the wires are in the ratio of $4/3$ and $2/3$, then the ratio of the currents passing through the wire will be
    View Solution
  • 9
    A milliammeter of range $10\, mA$ and resistance $9\, \Omega$ is joined in a circuit as shown. The meter gives full-scale deflection for current $I$ when $A$ and $B$ are used as its terminals, i.e., current enters at $A$ and leaves at $B$ ($C$ is left isolated). The value of $I$ is
    View Solution
  • 10
    For which of the following dependence of drift velocity $v$ on electric field $E$ is ohm's law obeyed
    View Solution