Here, the given equation of parabola is y2= 8x.
The equation of tangent to the parabola y2=8x is,
y= mx + 2/m
This tangent passes through the point (-2, 3)
So, 3 = -2m + 2/m
or, 3m + 2m2 = 2
or, 2m2+3m - 2= 0
or, 2m2 + (4 - 1)m -2 = 0
or, 2m2 + 4m - m - 2 = 0
or, 2m(m + 2) - 1(m+2) = 0
or, (m + 2) (2m - 1) = 0
Either, Or,
m = -2 m = 1/2
Required angle is,
Yes, a physical quantity can have magnitude and direction but still be a scalar if it doesn't obey the vector addition. An example is Electric Current which has magnitude and a fixed direction, but it does not follow vector laws of addition.
This picture develops a clear understanding.
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.