Question

A paper airplane with mass 0.1 kg is flying 1.5 m above the ground with a speed of 2 m/s. what is the total mechanical energy of the paper airplane?

Answer 1

Mechanical(ME) energy, in physical sciences, is the sum of kinetic energy (KE) and potential energy (PE). Below are the calculation in obtaining the energies,
 
     (1) KE =   0.5mv²     =  0.5(0.1 kg) x (2 m/s)² = 0.2 J
     (2) PE =    md          = (0.1 kg) x (1.5 m)        = 0.15 J
      (3) ME =  KE + PE = 0.2 J + 0.15 J               = 0.35 J

Thus, the mechanical energy is 0.35 Joules.