@hammad
u can go for physics it is a nice subject....also marks giving
but it also demands time...i think u have enough time as ur session is going to be ended in june-july so u have a 7-8 months for preparation,u can handle physics easily...and as for as applied math is concerned it is a BLESSING for u man as i know what is being taught to mech engrs in uet
applied maths contains statics,dynamics,vectors and tensors,numerical analysis etc
i think during ur engg u have gone through these subjects except tensors....so u can contct any electrical engg student for help as they go through this sub in their first or sec term

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Whatever mind can conceive,it can achieve - W.Clement Stone