Question
Sat August 27, 2011

# Why is current an scalar quantity ?

Sat August 27, 2011

For a physical quantity to be termed a vector quantity, having magnitude and direction is not enough. The quantity should obey the laws of vector addition too (like the triangle law or the parallelogram law). As we know, if two currents meet at a junction, the total current will be the algebraic sum of the two currents and not the vector sum. As the current does not require the vector laws to be applied and can be handled by simple algebra so it does not fit into the definition of a vector and hence it is a scalar.

Related Questions
Wed January 18, 2017

# A cell of emf E and internal resistance r is connected to two external resistance R1 and R2 and a perfect ammeter.The current in the circuit is measured in four different situation: (i)without any external resistance in the circuit (ii)with resistance R1 only (iii)with Ri and R2 in series combination (iv)with R1 and R2 in parallel combination The currents measured in the four cases are 0.42A,1.05A,1.4A and 4.2A,but not necessarily in that order.Identify the currents corresponding to the four cases mentioned above.

Thu November 24, 2016