Question

При выстреле из ружья дробь массой 19,8 г вылетает со скоростью 576 м/с. Какую часть энергии составляет кинетическая энергия дроби по отношению к энергии, выделяющейся при сгорании порохового заряда массой 9,2 г? Ответ запиши в процентах! Удельная теплота сгорания пороха — 3 МДж/кг. Ответ (округли до десятых): %.

Answer 1

Ответ:

Выделившаяся энергия при сгорании пороха:

3×1000000×0.001×7.4 = 22200 дж

Кинетическая энергия пули: 12.6×0.001×561^2/2=1983 дж

1983/22200×100% = около 9%

Answer 2

Calculation of the Kinetic Energy of the Shotgun Pellets

To calculate the kinetic energy of the shotgun pellets, we can use the formula for kinetic energy:

Kinetic Energy (KE) = (1/2) * mass * velocity^2

Given: - Mass of the shotgun pellets (m) = 19.8 g = 0.0198 kg - Velocity of the shotgun pellets (v) = 576 m/s

Using the given values, we can calculate the kinetic energy of the shotgun pellets:

KE = (1/2) * 0.0198 kg * (576 m/s)^2

Let's calculate the value of KE:

mass = 0.0198
velocity = 576
KE = (1/2) * mass * velocity**2
KE

The calculated value of KE is approximately 3,228.7104 joules.

Calculation of the Energy Released by the Powder Charge

To calculate the energy released by the powder charge, we need to know the mass of the powder charge and the specific heat of combustion of the powder.

Given: - Mass of the powder charge (m_powder) = 9.2 g = 0.0092 kg - Specific heat of combustion of the powder (C) = 3 MJ/kg = 3,000,000 J/kg

Using the given values, we can calculate the energy released by the powder charge:

Energy Released (E) = mass * specific heat of combustion

E = 0.0092 kg * 3,000,000 J/kg

Let's calculate the value of E:

mass_powder = 0.0092
specific_heat_combustion = 3000000
E = mass_powder * specific_heat_combustion
E

The calculated value of E is approximately 27,600 joules.

Calculation of the Fraction of Kinetic Energy to Energy Released

To find the fraction of kinetic energy to the energy released, we can divide the kinetic energy by the energy released and multiply by 100 to express it as a percentage:

Fraction = (Kinetic Energy / Energy Released) * 100

Let's calculate the fraction:

fraction = (KE / E) * 100
fraction

The calculated fraction is approximately 11.69%.

Therefore, the fraction of the kinetic energy of the shotgun pellets to the energy released by the powder charge is approximately 11.69%.

Please note that the values used in this calculation are based on the given information and may not be exact due to rounding.