Question

РЕБЯТ ОЧЕНЬ ПРОШУ ПОМОГИТЕ... РЕШАЕТСЯ МОЯ ОЦЕНКА МЕЖДУ 4 и 5...Помогите решить """"""""""""С какой скоростью должна лететь пуля, чтобы при ударе о преграду она расплавилась, если температура пули до удара 57 градусов по цельсию? При ударе в тело превращается 40% энергии пули."""""""""""""""""" "надо применить закон сохранения энергии"

Answer 1

Дано t1=57C   t2=327C   k=0,4    V-?

летящая пуля обладает энергией E=m*V^2/2

Q=E*k=Q1+Q2=c*m*(t2-t1)+л*m
k*m*V^2/2=c*m*(t2-t1)+л*m

V=√2*(c*(t2-t1)+л)/k=√(2*130*(327-57)+л)/0,4=√(260*270+25000)/0,4=487,85 м/с

Answer 2

Calculation of the Bullet's Required Speed

To determine the speed at which the bullet should travel in order to melt upon impact, we can apply the law of conservation of energy. According to this law, the initial kinetic energy of the bullet will be converted into heat energy upon impact.

The formula for kinetic energy is:

KE = (1/2)mv^2

Where: - KE is the kinetic energy - m is the mass of the bullet - v is the velocity of the bullet

Since we are given that 40% of the bullet's energy is converted into heat, we can write:

0.4 * KE = Q

Where: - Q is the heat energy produced upon impact

To calculate the heat energy produced, we can use the formula:

Q = mcΔT

Where: - m is the mass of the bullet - c is the specific heat capacity of the bullet material - ΔT is the change in temperature

Given that the initial temperature of the bullet is 57 degrees Celsius, we can calculate the change in temperature as:

ΔT = Tf - Ti

Where: - Tf is the final temperature (the melting point of the bullet material) - Ti is the initial temperature

To find the melting point of the bullet material, we need to know the specific material used. Unfortunately, the search results provided do not contain the necessary information to determine the specific heat capacity or melting point of the bullet material. Therefore, we are unable to provide a specific answer to your question.

If you have any other questions or need further assistance, feel free to ask!