LAW'S OF RESISTANCE

LAW'S OF RESISTANCE

The RESISTANCE of a Conductor varies,

  • Directly with its LENGTH.
  • Inversely to its CROSS-SECTIONAL AREA.
  • Depends on NATURE of the materials.
  • Depends on the TEMPERATURE.
                                      R ∝ L,  R ∝ 1/ A
                                      R ∝ L/A
                                      R = ρ * (L/A)

Where ρ is called SPECIFIC RESISTANCE (RESISTIVITY) and its unit is Ohm-Mtr.







For More Topics:


Follow Us ON:

Comments

Post a Comment

Popular posts from this blog

TRANSFORMER RATING CALCULATION

Image
 TRANSFORMER RATING CALCULATION In this BLOG, we are going t discuss about the Calculation of   TRANSFORMER RATING : For Eg:- Maximum Load = 400KW. Diversity Factor = 0.7 Therefore, Expected Load in KW = 400*0.7 = 280KW Expected Load in KVA = 280/ 0.9 = 311KVA (Power Factor Considered as 0.9) 85% Loading Capacity is considered. Required KVA Rating = 311/ 0.85 = 366KVA Therefore, 400KVA transformer is used.  (400KVA is the n ext Available Rating above 366KVA) For More Topics: Follow Us On: FACEBOOK
Read more

CONDUCTANCE & CONDUCTIVITY

Image
CONDUCTANCE It is the measure of how easily the current will flow through the conductor. The reciprocal of Resistance is called CONDUCTANCE and is denoted by "G" . Its unit is "MHO" or "SIEMENS".          G = 1/R = I/V. CONDUCTIVITY Conductivity or SPECIFIC CONDUCTANCE is the reciprocal of specific resistance. It represented as σ (SIGMA) and its unit is Mho/Mtr. σ  = 1/  ρ. For More Topics: Follow Us On: FACEBOOK
Read more