Yes, a vector which has zero magnitude is also a vector in case of two vectors travelling in opposite directions with equal magnitudes. At this case, the resultant vector has zero magnitude but it is still a vector. We call it a null vector.
Yes, if the angle between the two vectors is more than 90o but less than 2700. (cosΘ is negative)
In mitosis, the prophase is further understood by dividing it into the given sub-stages:
1.Leptotene :
In this stage the nucleus enlarges in size in the chromosome. The chromosomes appear thin, thread-like and single-stranded in this stage. They have swollen or beaded structures along their length and their ends appear converged towards one side of the nucleus called bouquet.
2.Zygotene:
In this stage, the identical chromosomes come together and form bivalent or homologous pairs. Further, ...
The Wheatstone bridge is not suitable for measuring very low resistance because it is based on a ratio of two resistances, and the resolution of the bridge decreases as the ratio approaches 1. This means that the Wheatstone bridge is not accurate enough to measure very small changes in resistance.
