Solving Force of 17g Bullet Accelerated in Rifle Barrel

[xlogit3k]

Homework Statement

A 17 g bullet is accelerated in a rifle barrel
103 cm long to a speed of 392 m/s.
Use the work-energy theorem to find the
average force exerted on the bullet while it is
being accelerated.
Answer in units of N.

Homework Equations

The Attempt at a Solution

No idea how to start this problem

 

[collinsmark]

No idea how to start this problem

Why not start with the work-energy theorem?

 

[xlogit3k]

Why not start with the work-energy theorem?

Wnet= 1/2mv^2(final)-1/2mv^2(initial)

i don't know what numbers to put in

 

[collinsmark]

Wnet= 1/2mv^2(final)-1/2mv^2(initial)

i don't know what numbers to put in

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).

 

[xlogit3k]

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).

force x distance

 

[collinsmark]

force x distance

That's right! (Well, technically it's the dot product of force and displacement). Now you should have enough to solve the problem.