The discussion focuses on calculating the average force exerted on a 17 g bullet accelerated to a speed of 392 m/s within a 103 cm rifle barrel using the work-energy theorem. The key equation utilized is Wnet = 1/2 mv^2(final) - 1/2 mv^2(initial), where the initial velocity is 0 m/s. Participants emphasize the importance of understanding that work is defined as the product of force and displacement, leading to the conclusion that the average force can be derived from the work done over the distance of the barrel.
PREREQUISITESPhysics students, educators, and anyone interested in understanding the principles of mechanics and ballistics, particularly in relation to the work-energy theorem and force calculations.
Why not start with the work-energy theorem?xlogit3k said:No idea how to start this problem
collinsmark said:Why not start with the work-energy theorem?
Well, you know the initial velocity is 0 and the final velocity is 392 m/s.xlogit3k said:Wnet= 1/2mv^2(final)-1/2mv^2(initial)
i don't know what numbers to put in
collinsmark said:Well, you know the initial velocity is 0 and the final velocity is 392 m/s.
But there is also something else you'll need. What is the very definition of work? (Hint: it's a function of force and displacement).
That's right! (Well, technically it's the dot product of force and displacement). Now you should have enough to solve the problem.xlogit3k said:force x distance