Question

Определите полную механическую энергию стрелы массой 300г движущейся на высоте 5м со скоростью 4м/с

Answer 1

1) Eпотенциал.= 0,3 кг*4 м/с*5 м=6 Дж 2) Екин=0,3 кг* ( 4*4 ) м/с: 2=2,4Дж. 3)Еполн= 6+2,4= 8,4 Дж

Answer 2

Calculation of the Total Mechanical Energy of an Arrow

To calculate the total mechanical energy of an arrow, we need to consider both its kinetic energy and potential energy.

The kinetic energy (KE) of an object is given by the equation:

KE = (1/2) * m * v^2

where: - KE is the kinetic energy, - m is the mass of the object, and - v is the velocity of the object.

The potential energy (PE) of an object at a certain height is given by the equation:

PE = m * g * h

where: - PE is the potential energy, - m is the mass of the object, - g is the acceleration due to gravity (approximately 9.8 m/s^2), and - h is the height of the object.

To find the total mechanical energy (E) of the arrow, we can add the kinetic energy and potential energy together:

E = KE + PE

Now, let's calculate the total mechanical energy of the arrow with the given values:

- Mass of the arrow (m) = 300 g = 0.3 kg - Height of the arrow (h) = 5 m - Velocity of the arrow (v) = 4 m/s

Using the equations mentioned above, we can calculate the kinetic energy (KE) and potential energy (PE) of the arrow:

KE = (1/2) * m * v^2 KE = (1/2) * 0.3 * (4^2) KE = 0.3 * 8 KE = 2.4 J

PE = m * g * h PE = 0.3 * 9.8 * 5 PE = 1.47 J

Now, let's calculate the total mechanical energy (E) by adding the kinetic energy and potential energy:

E = KE + PE E = 2.4 + 1.47 E = 3.87 J

Therefore, the total mechanical energy of the arrow with a mass of 300 g, moving at a height of 5 m with a velocity of 4 m/s, is approximately 3.87 Joules.