conservation of energy quiz

Hii! 😄 Sorry your post got ghosted for a bit.

Here’s how I think about it:

1️⃣ Energy Balance Rule
Whenever you’re dealing with a closed system (like a bouncing ball), energy isn’t destroyed—it just changes form. Some of it becomes “non-useful,” like heat or sound.

• UGi (Initial Energy): Think of this as your “energy budget” at the start.

• Thermal (Energy Loss): This is the “tax” the environment takes—energy lost to friction, air, or sound.

• UGf (Final Energy): What’s left over for the ball to bounce back up.

2️⃣ Spotting When to Use It
You’ll know to use this formula when the problem gives you three clues:

• A start and end state (like the ball’s heights at two points).

• Mentions of energy loss (heat, friction, air resistance).

• Velocity is zero at both points (the ball is at rest at the top and bottom).

3️⃣ The Logic Flow
If the world were perfect and frictionless, the ball would bounce back to the same height—UGf = UGi. But the problem says some energy was converted to heat (like 0.15 J), so basically:

"What I end up with = What I started with – what got lost along the way."

hope this helps!