Question

Определите полную механическую энергию космического корабля массой 2т, движущегося на высоте 300км со скоростью 20 м/с

Answer 1

Mv²/2+mgh≡E
2000*400/2+2000*10*300000≡6000400kgJ 

Answer 2

Calculation of the Total Mechanical Energy of a Spacecraft

To determine the total mechanical energy of a spacecraft, we need to consider both its kinetic energy and potential energy.

Given: - Mass of the spacecraft (m) = 2 tons = 2000 kg - Height above the Earth's surface (h) = 300 km = 300,000 m - Velocity of the spacecraft (v) = 20 m/s

Kinetic Energy (KE)

The kinetic energy of an object is given by the formula:

KE = (1/2)mv^2

where: - m is the mass of the object - v is the velocity of the object

Substituting the given values:

KE = (1/2)(2000 kg)(20 m/s)^2

Simplifying the equation:

KE = 400,000 J

Potential Energy (PE)

The potential energy of an object at a certain height above the Earth's surface is given by the formula:

PE = mgh

where: - m is the mass of the object - g is the acceleration due to gravity (approximately 9.8 m/s^2) - h is the height above the Earth's surface

Substituting the given values:

PE = (2000 kg)(9.8 m/s^2)(300,000 m)

Simplifying the equation:

PE = 5,880,000,000 J

Total Mechanical Energy (E)

The total mechanical energy of the spacecraft is the sum of its kinetic energy and potential energy:

E = KE + PE

Substituting the calculated values:

E = 400,000 J + 5,880,000,000 J

Simplifying the equation:

E = 5,880,400,000 J

Therefore, the total mechanical energy of the spacecraft is approximately 5,880,400,000 Joules.

Please note that the above calculations assume that there are no other significant forms of energy (such as thermal or electromagnetic energy) present in the spacecraft.