Explain the nature of Post-Traumatic Stress Disorder (PTSD).
Points:
(i) Meaning
(ii) Shock stage
(iii) Suggestible stage
(iv) Recovery stage
Derive an expression for maximum speed of a vehicle moving along a horizontal circular track.
Predict the type of cubic lattice of a solid element having edge length of 400 pm and density of 6.25 g/ml.
(Atomic mass of element = 60)