A 4 g bullet leaves the muzzle of a riffle with a speed of 350 m s-1. What force is exerted on the bullet when it is travelling down the 0.85 m long barrel of the rifle?
F = m*a
V^2 = Vo^2 + 2a*d
a = (V^2-Vo^2)/2d
a = ((350)^2-0)/1.7 = 72,059 m/s^2
F = 0.004 * 72059 = 288 N.
To find the force exerted on the bullet, we can use the equation:
Force = mass x acceleration
First, we need to find the acceleration of the bullet. We can use the equation:
acceleration = (final velocity - initial velocity) / time
Since the bullet leaves the muzzle of the rifle, we can assume that the initial velocity is zero. Therefore, the equation simplifies to:
acceleration = final velocity / time
To find the time it takes for the bullet to travel down the barrel, we can use the equation:
time = distance / speed
Given that the distance is 0.85 m and the speed is 350 m/s, we can substitute these values into the equation and calculate the time:
time = 0.85 m / 350 m/s
Now, we can substitute the time value into the acceleration equation to find the acceleration:
acceleration = (350 m/s) / (0.85 m / 350 m/s)
After calculating the acceleration, we can substitute the mass of the bullet into the force equation to find the force:
Force = (4 g) x acceleration
Note that the mass of the bullet needs to be converted to kilograms before substituting it into the equation. Since 1 g = 0.001 kg, the mass of the bullet in kilograms is:
mass = 4 g x (0.001 kg / 1 g)
Finally, substitute the mass and acceleration values into the equation and calculate the force.