# Electricity - Plz Help!

By considering a wire of radius 'r', lenght 'l' and resistivity 'e' through which a current I flows, show that

a) the rate of production of heat by it is I^2*P*l / pi*r^2

b) the rate of loss of heat from its surface is 2pi*r*t*h , where 'h' is the heat lost per unit area of surface per second.

1. 👍 0
2. 👎 0
3. 👁 110

## Similar Questions

1. ### Physics

What is the resistivity of a cylinderical material wire whose 1.0m lenght has a resistance of 2.0 ohm? The radius of the wire is 1.0mm

asked by Mercy on January 3, 2016
2. ### physics

Consider two copper wires with the same cross-sectional area. Wire A is twice as long as wire B. How do the resistivities and resistances of the two wires compare? CHECK ALL THAT APPLY Wire A and wire B have the same resistance.

asked by Anonymous on February 7, 2014
3. ### physics

You apply a potential difference of 5.00 V between the ends of a wire that is 2.65 m in length and 0.654 mm in radius. The resulting current through the wire is 17.6 A. What is the resistivity of the wire?

asked by Dan on October 20, 2013
4. ### physics

A tungsten wire has a radius of 0.077 mm and is heated from 20.0 to 1205 °C. The temperature coefficient of resistivity is α = 4.5 10-3 (C°)−1. When 110 V is applied across the ends of the hot wire, a current of 1.3 A is

asked by Dee on January 27, 2014
5. ### Physics

Number 10 aluminum wire (radius= 1.3 mm) is commonly used for electrical installations in homes. What is the voltage drop in 20 m of this wire if it carries a current of 10 Amps? The bulk resistivity of aluminum is 2.7*10^-8 Ohm*m

asked by Jessica on October 30, 2010
6. ### physics

a toaster with 4m length of nichrome(resistivity is 150Ã—10^-8 and temperature coefficient of resistivity is 0.4Ã—10^-3/Â¤c) wire as its heating element is rated at 1050w and operates on 220v.the operating temperature of

asked by Anonymous on July 12, 2018
7. ### Electricity help needed please

Two spherical conducting wires A and B are connected to the same potential difference. Wire A is three times as long as wire B, with a radius double that of wire B and resistivity doubles that of wire B. What is the power

asked by Abdu on November 15, 2013
8. ### physics

Two spherical conducting wires A and B are connected to the same potential difference. Wire A is three times as long as wire B, with a radius double that of wire B and resistivity doubles that of wire B. What is the ratio power

asked by Anonymous on November 14, 2013
9. ### physics

Two spherical conducting wires A and B are connected to the same potential difference. Wire A is three times as long as wire B, with a radius double that of wire B and resistivity doubles that of wire B. What is the power

asked by Anton on November 13, 2013
10. ### physics

The filament in an incandescent light bulb is made from tungsten (resistivity 5.6 x 10-8 Ù·m). The light bulb is plugged into a 120-V outlet and draws a current of 2.36 A. If the radius of the tungsten wire is 0.00464 mm, how

asked by james small help plz on October 10, 2015

More Similar Questions