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.
1.ans: No the tension in the string of a simple pendulum is not constant throughout the motion
v is velocity of the bob and theta is the angle made by the string with vertical axis.as v and both are variable T is also variable.T is maximum at mean position as at mean position v is max and the angle is minimum.
2.ans: If the amplitude of the simple...
Materials show varying behaviors based on their Poisson's ratio. High Poisson's ratio materials (near 0.5) contract significantly sideways when stretched and expand when compressed, seen in substances like rubber. Low Poisson's ratio materials (near 0) undergo minimal width change during axial deformation, typical of metals and common engineering materials.