Determine the mass of the rocket, which at the moment of takeoff has a speed of v = 180 m / s

Determine the mass of the rocket, which at the moment of takeoff has a speed of v = 180 m / s and a kinetic energy of K = 16.2 kJ.

Given:

v = 180 meters per second – the speed that the rocket had at the time of takeoff;

E = 16.2 kJ is the kinetic energy of the rocket.

It is required to determine m (kilogram) – the mass of the rocket.

Let’s convert units of measurement of energy from kilojoules to joules:

E = 16.2 kJ = 16.2 * 1000 = 16200 Joules.

Then, to determine the mass, you must use the following formula:

E = m * v ^ 2/2, from here we find that:

m = 2 * E / v ^ 2 = 2 * 16200/180 ^ 2 = 32400/32400 = 1 kilogram.

Answer: the mass of the rocket is 1 kilogram.