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# Tag Archives: scalar quantity

## Difference between dot product and cross product

Shashi Kant asked:

“What is difference between cross product and dot product?”

Answer:

If the product of two vectors is a scalar quantity it is called scalar product or dot product.

If the product of two vectors is a vector quantity it is called vector product or cross product.

## Why Electric Current is a Scalar Quantity?

Vaishali asks:

“Why is current a scalar quantity even after having both magnitude as well as direction?”

Answer:

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 of the resultant current will be the **algebraic sum ** of the two current and not the **vector sum.**