Which of the following equations is dimensionally correct, where: E is energy, J; F is thrust, N ) ; r is density, kgm - 3 ; k is a non - dimensional constant m is mass, kg; r = radius, m; u = velocity, m / s , A = Area, m 2 ; R = gas constant, J / ( kg K ) T is Temperature, K .
i ) E / U = F / m ,
ii ) EU = mF ,
iii ) E = F / A ,
iv ) E = r U A ,
v ) E = r U 3 A ,
vi ) E t 2 = kr 5 r ,
vii ) E = kF / U ,
viii ) none of the above