Question

What speed would a fly with a mass of 0.72 g need in order to have the same kinetic energy as a 1250 kg automobile traveling at a speed of 11 m/s?

Answer 1

Kinetic of automobile

Mass m = 1,250 Kg;         V = 11 m/s

Formula: K.E = 1/2 mV²

               K.E = 1/2(1,250 Kg)(11 m/s)²

               K.E = 75,625 J

Speed required for insect to have the same kinetic energy as automobile

Mass of insect = 0.72 g convert to Kg   m = 7.2 x 10⁻⁴ Kg

K.E = 1/2 mV²  Derive V =?

 V = 2 K.E/m

 V = √2(75,625 J)/7.2 x 10⁻4 Kg

 V = √2.1 x 10⁸ m²/s²

 V = 14,491.34 m/s  (velocity of insect)