Question

Пуля,двигающаяся в стволе ружья t=0,002с,вылетает со скоростью v=500 м/с .определить : а)а-ускорение,с которым двигалась пуля.б)l-длину ствола ружья(напишите решение пожалуйста,дано инайти есть)

Answer 1

Дано:
t=0,002 с
v=500 м/с
Найти: а, l
Решение:
Вначале пуля покоилась.
Формула скорости при движении без начальной скорости
v=at
Отсюда находим ускорение
a=v/t=500/0.002=250000 (м/с²)
Длина ствола - это путь, пройденный телом при разгоне. Формула пути:
l=s=at²/2=250000*0.002²/2=0.5 (м)
Ответ: а) 250000 м/с²; б) 0,5 м

Answer 2

Problem Analysis

We are given the initial time `t = 0.002 s` and the initial velocity `v = 500 m/s` of a bullet moving in the barrel of a rifle. We need to determine the acceleration `a` with which the bullet was moving and the length `l` of the rifle barrel.

Solution

To find the acceleration `a`, we can use the equation of motion:

v = u + at

where: - `v` is the final velocity (which is equal to the initial velocity since the bullet leaves the barrel), - `u` is the initial velocity, - `a` is the acceleration, and - `t` is the time.

Since the final velocity `v` is equal to the initial velocity `u`, we can rewrite the equation as:

u = u + at

Simplifying the equation, we get:

0 = at

Since the time `t` is not zero, the only way for the equation to hold true is if the acceleration `a` is zero. Therefore, the acceleration of the bullet is zero.

To find the length `l` of the rifle barrel, we can use the equation of motion:

s = ut + (1/2)at^2

where: - `s` is the displacement (which is equal to the length of the barrel), - `u` is the initial velocity, - `a` is the acceleration, and - `t` is the time.

Since the acceleration `a` is zero, the equation simplifies to:

s = ut

Substituting the given values, we have:

l = v * t

Calculating the value, we get:

l = 500 m/s * 0.002 s = 1 meter

Therefore, the length of the rifle barrel is 1 meter.

Summary

In summary, the acceleration of the bullet is zero, and the length of the rifle barrel is 1 meter.