The _______________ an object, the more strongly its molecules ___________________; this vibration is a form of energy called _______________________ energy.

(Its a fill in the blank. I'm very confused about this and I can't find the answer in my book. Please help me!)

The answer to your question is as follows:

The tighter an object is packed, the more strongly its molecules vibrate; this vibration is a form of energy called thermal energy.

To understand this concept, we can break it down:

1. The first blank asks for a word to describe how an object is packed. The word that fills this blank is "tighter." When objects are tightly packed, their molecules are close together.

2. The second blank asks for a verb to describe what the molecules do when they are packed tightly. The appropriate verb for this is "vibrate." When the molecules are tightly packed, they vibrate more strongly.

3. The third blank asks for a term to describe the energy associated with the vibration of molecules. In this case, the term is "thermal energy." Thermal energy refers to the kinetic energy of particles as they move and vibrate.

To summarize:

The tighter an object is packed, the more strongly its molecules vibrate; this vibration is a form of energy called thermal energy.