152724
A constant voltage is applied between the two ends of a metallic wire. If both the length and the radius of the wire are doubled, the rate of heat developed in the wire
1 will be doubled
2 will be halved
3 will be remain the same
4 will be quadrupled
Explanation:
A The heat produced in the metallic wire is given using, $H=\frac{V^{2} \times t}{R}$ $\text { As, } R=\frac{\rho \times L}{A}$ $\text { or } H=\frac{V^{2} \times t \times \pi \times r^{2}}{\rho \times L}$ Therefore, heat produced will be doubled if both length and the radius of the wire are doubled.
CG PET- 2004
Current Electricity
152737
A $10 \Omega$ electric heater operates on a $110 \mathrm{~V}$ line. The rate at which heat is developed in watts is:
152738
Heat produced (cals) in a resistance $R$ when a current $I$ amperes flows through it for $t$ seconds is given by the expression:
1 $\frac{\mathrm{I}^{2} \mathrm{Rt}}{4.2}$
2 $\frac{\mathrm{IR}^{2} \mathrm{t}}{4.2}$
3 $\frac{4.2 \mathrm{It}}{\mathrm{t}^{2}}$
4 $\frac{\mathrm{IRt}^{2}}{4.2}$
5 $\frac{4.2}{\mathrm{I}^{2} \mathrm{Rt}}$
Explanation:
A The heat generation across a resister of resistance $\mathrm{R}$, a wire in time $\mathrm{t}$. $\mathrm{I}$ is given current. $\mathrm{H}=\mathrm{I}^{2}$ Rt Joules $1 \mathrm{cal}=4.2 \mathrm{~J}$ $\mathrm{H}=\frac{\mathrm{I}^{2} \mathrm{Rt}}{4.2} \text { Calories }$
Kerala CEE 2004
Current Electricity
152744
Which of the following is a correct statement?
1 Heat producted in a conductor varies directly as the current flowing.
2 Heat produced in a conductor varies inversely as the current flowing.
3 Heat produced in a conductor varies directly as the square of the current flowing.
4 Heat produced in a conductor varies inversely as the square of the circuit flowing.
Explanation:
C According to Joule's law of heating heat produced in a conductor. $\mathrm{H}=1^{2} \mathrm{Rt}$ Heat produced in a conductor varies directly as the square of the current flowing.
152724
A constant voltage is applied between the two ends of a metallic wire. If both the length and the radius of the wire are doubled, the rate of heat developed in the wire
1 will be doubled
2 will be halved
3 will be remain the same
4 will be quadrupled
Explanation:
A The heat produced in the metallic wire is given using, $H=\frac{V^{2} \times t}{R}$ $\text { As, } R=\frac{\rho \times L}{A}$ $\text { or } H=\frac{V^{2} \times t \times \pi \times r^{2}}{\rho \times L}$ Therefore, heat produced will be doubled if both length and the radius of the wire are doubled.
CG PET- 2004
Current Electricity
152737
A $10 \Omega$ electric heater operates on a $110 \mathrm{~V}$ line. The rate at which heat is developed in watts is:
152738
Heat produced (cals) in a resistance $R$ when a current $I$ amperes flows through it for $t$ seconds is given by the expression:
1 $\frac{\mathrm{I}^{2} \mathrm{Rt}}{4.2}$
2 $\frac{\mathrm{IR}^{2} \mathrm{t}}{4.2}$
3 $\frac{4.2 \mathrm{It}}{\mathrm{t}^{2}}$
4 $\frac{\mathrm{IRt}^{2}}{4.2}$
5 $\frac{4.2}{\mathrm{I}^{2} \mathrm{Rt}}$
Explanation:
A The heat generation across a resister of resistance $\mathrm{R}$, a wire in time $\mathrm{t}$. $\mathrm{I}$ is given current. $\mathrm{H}=\mathrm{I}^{2}$ Rt Joules $1 \mathrm{cal}=4.2 \mathrm{~J}$ $\mathrm{H}=\frac{\mathrm{I}^{2} \mathrm{Rt}}{4.2} \text { Calories }$
Kerala CEE 2004
Current Electricity
152744
Which of the following is a correct statement?
1 Heat producted in a conductor varies directly as the current flowing.
2 Heat produced in a conductor varies inversely as the current flowing.
3 Heat produced in a conductor varies directly as the square of the current flowing.
4 Heat produced in a conductor varies inversely as the square of the circuit flowing.
Explanation:
C According to Joule's law of heating heat produced in a conductor. $\mathrm{H}=1^{2} \mathrm{Rt}$ Heat produced in a conductor varies directly as the square of the current flowing.
152724
A constant voltage is applied between the two ends of a metallic wire. If both the length and the radius of the wire are doubled, the rate of heat developed in the wire
1 will be doubled
2 will be halved
3 will be remain the same
4 will be quadrupled
Explanation:
A The heat produced in the metallic wire is given using, $H=\frac{V^{2} \times t}{R}$ $\text { As, } R=\frac{\rho \times L}{A}$ $\text { or } H=\frac{V^{2} \times t \times \pi \times r^{2}}{\rho \times L}$ Therefore, heat produced will be doubled if both length and the radius of the wire are doubled.
CG PET- 2004
Current Electricity
152737
A $10 \Omega$ electric heater operates on a $110 \mathrm{~V}$ line. The rate at which heat is developed in watts is:
152738
Heat produced (cals) in a resistance $R$ when a current $I$ amperes flows through it for $t$ seconds is given by the expression:
1 $\frac{\mathrm{I}^{2} \mathrm{Rt}}{4.2}$
2 $\frac{\mathrm{IR}^{2} \mathrm{t}}{4.2}$
3 $\frac{4.2 \mathrm{It}}{\mathrm{t}^{2}}$
4 $\frac{\mathrm{IRt}^{2}}{4.2}$
5 $\frac{4.2}{\mathrm{I}^{2} \mathrm{Rt}}$
Explanation:
A The heat generation across a resister of resistance $\mathrm{R}$, a wire in time $\mathrm{t}$. $\mathrm{I}$ is given current. $\mathrm{H}=\mathrm{I}^{2}$ Rt Joules $1 \mathrm{cal}=4.2 \mathrm{~J}$ $\mathrm{H}=\frac{\mathrm{I}^{2} \mathrm{Rt}}{4.2} \text { Calories }$
Kerala CEE 2004
Current Electricity
152744
Which of the following is a correct statement?
1 Heat producted in a conductor varies directly as the current flowing.
2 Heat produced in a conductor varies inversely as the current flowing.
3 Heat produced in a conductor varies directly as the square of the current flowing.
4 Heat produced in a conductor varies inversely as the square of the circuit flowing.
Explanation:
C According to Joule's law of heating heat produced in a conductor. $\mathrm{H}=1^{2} \mathrm{Rt}$ Heat produced in a conductor varies directly as the square of the current flowing.
152724
A constant voltage is applied between the two ends of a metallic wire. If both the length and the radius of the wire are doubled, the rate of heat developed in the wire
1 will be doubled
2 will be halved
3 will be remain the same
4 will be quadrupled
Explanation:
A The heat produced in the metallic wire is given using, $H=\frac{V^{2} \times t}{R}$ $\text { As, } R=\frac{\rho \times L}{A}$ $\text { or } H=\frac{V^{2} \times t \times \pi \times r^{2}}{\rho \times L}$ Therefore, heat produced will be doubled if both length and the radius of the wire are doubled.
CG PET- 2004
Current Electricity
152737
A $10 \Omega$ electric heater operates on a $110 \mathrm{~V}$ line. The rate at which heat is developed in watts is:
152738
Heat produced (cals) in a resistance $R$ when a current $I$ amperes flows through it for $t$ seconds is given by the expression:
1 $\frac{\mathrm{I}^{2} \mathrm{Rt}}{4.2}$
2 $\frac{\mathrm{IR}^{2} \mathrm{t}}{4.2}$
3 $\frac{4.2 \mathrm{It}}{\mathrm{t}^{2}}$
4 $\frac{\mathrm{IRt}^{2}}{4.2}$
5 $\frac{4.2}{\mathrm{I}^{2} \mathrm{Rt}}$
Explanation:
A The heat generation across a resister of resistance $\mathrm{R}$, a wire in time $\mathrm{t}$. $\mathrm{I}$ is given current. $\mathrm{H}=\mathrm{I}^{2}$ Rt Joules $1 \mathrm{cal}=4.2 \mathrm{~J}$ $\mathrm{H}=\frac{\mathrm{I}^{2} \mathrm{Rt}}{4.2} \text { Calories }$
Kerala CEE 2004
Current Electricity
152744
Which of the following is a correct statement?
1 Heat producted in a conductor varies directly as the current flowing.
2 Heat produced in a conductor varies inversely as the current flowing.
3 Heat produced in a conductor varies directly as the square of the current flowing.
4 Heat produced in a conductor varies inversely as the square of the circuit flowing.
Explanation:
C According to Joule's law of heating heat produced in a conductor. $\mathrm{H}=1^{2} \mathrm{Rt}$ Heat produced in a conductor varies directly as the square of the current flowing.
