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I'm stuck in in school suspension and I have to finish this quiz (it's open note/technology, not cheating!) by the end of school today, and I can't seem to find a problem similar to this on the internet, so I'm coming here. If you want like, I dunno, a poem or a drawing or something, I'll give ya what I can if you help me quickly.

A 0.017 kg bullet with a velocity of 380 m/s strikes a 2.5 kg block inelastically. The block is suspended to the ceiling by 2 strings that are 1.5m long. The height from the floor to the block is 1.25 m.

I've done a and b (answers below), but the two strings are throwing me for a loop on the other ones.

c. The maximum horizontal displacement of the block from its rest position following the collision.

d. The maximum vertical displacement of the block following the collision.

e. The angle between the ceiling and the strings when the block reaches the highest position.

f. The tension in each string when the block swings back to its lowest position.

I've figured out the speed of the block after the collision is 2.56 m/s through the momentum equations, and I've also figured out the kinetic energy of the bullet before the collision is 1227.4 J, while the block's kinetic energy after is 8.192 J.

m1v1 +m2v2 = (m1 + m2)v

Kbottom = Utop, or 1/2(m1 +m2)v^2 = (m1 +m2)gh

The sine and cosine equations

So, I know if this were one string, I would make a use the LOCOE above to find the height travelled and then make a triangle with the original given height as the hypotenuse and the h I got subtracted from it as the y. I could use inverse cosine to find the angle, and find the x to find the horizontal displacement. But what do I do differently when there are two strings?

Edit: Also, I've read the FAQ and I'm sorry for putting urgent! Didn't meant to pressure anyone. Thank you for all the help I've received so far, you guys honestly don't know how much I appreciate it. =)

## Homework Statement

A 0.017 kg bullet with a velocity of 380 m/s strikes a 2.5 kg block inelastically. The block is suspended to the ceiling by 2 strings that are 1.5m long. The height from the floor to the block is 1.25 m.

I've done a and b (answers below), but the two strings are throwing me for a loop on the other ones.

c. The maximum horizontal displacement of the block from its rest position following the collision.

d. The maximum vertical displacement of the block following the collision.

e. The angle between the ceiling and the strings when the block reaches the highest position.

f. The tension in each string when the block swings back to its lowest position.

I've figured out the speed of the block after the collision is 2.56 m/s through the momentum equations, and I've also figured out the kinetic energy of the bullet before the collision is 1227.4 J, while the block's kinetic energy after is 8.192 J.

## Homework Equations

m1v1 +m2v2 = (m1 + m2)v

Kbottom = Utop, or 1/2(m1 +m2)v^2 = (m1 +m2)gh

The sine and cosine equations

## The Attempt at a Solution

So, I know if this were one string, I would make a use the LOCOE above to find the height travelled and then make a triangle with the original given height as the hypotenuse and the h I got subtracted from it as the y. I could use inverse cosine to find the angle, and find the x to find the horizontal displacement. But what do I do differently when there are two strings?

Edit: Also, I've read the FAQ and I'm sorry for putting urgent! Didn't meant to pressure anyone. Thank you for all the help I've received so far, you guys honestly don't know how much I appreciate it. =)

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