Question

target reading skill building vocabulary use your definitions to help answer the questions. reviewing key concepts 1. a. defining what is mechanical energy? b. drawing conclusions if an objects mechanical energy is equal to its potential energy, how much kinetic energy does the object have? how do you know? c. calculating if the kinetic energy of a falling apple is 5.2 j and its potential energy is 3.5 j, what is its mechanical energy? 2. a. listing list the five forms of energy associated with the particles that make up objects. b. explaining why do the particles of objects have both kinetic and potential energy? c. classifying what kind of energy do you experience when you eat a peanut butter and jelly sandwich?

Explanation:

Step1: Define mechanical energy

Mechanical energy ($E_m$) is the sum of kinetic energy ($E_k$) and potential energy ($E_p$), i.e., $E_m=E_k + E_p$.

Step2: Answer part 1b

If $E_m = E_p$, then from $E_m=E_k + E_p$, we substitute to get $E_p=E_k + E_p$. Subtracting $E_p$ from both sides gives $E_k = 0$. We know this because the formula for mechanical energy is the sum of the two, and when mechanical energy equals potential energy, kinetic energy must be zero.

Step3: Answer part 1c

Given $E_k=5.2\ J$ and $E_p = 3.5\ J$, using $E_m=E_k + E_p$, we substitute the values: $E_m=5.2+3.5=8.7\ J$.

Step4: Answer part 2a

The five forms of energy associated with particles are chemical - potential energy (stored in chemical bonds), electrical energy (due to charged particles), thermal energy (kinetic energy of particles), nuclear energy (stored in atomic nuclei), and electromagnetic energy (associated with electromagnetic fields).

Step5: Answer part 2b

Particles of objects have kinetic energy because they are in constant motion (vibration, rotation, translation). They have potential energy because of their position relative to other particles (e.g., in a bond or in a field).

Step6: Answer part 2c

When you eat a peanut - butter and jelly sandwich, you experience chemical energy. The food contains stored chemical energy in its molecular bonds which is released during digestion and metabolism.

Answer:

1.a. Mechanical energy is the sum of kinetic and potential energy.
1.b. The object has 0 kinetic energy. Since $E_m = E_k+E_p$ and $E_m = E_p$, then $E_k = 0$.
1.c. 8.7 J
2.a. Chemical - potential, electrical, thermal, nuclear, electromagnetic.
2.b. Particles are in motion (kinetic) and have position relative to others (potential).
2.c. Chemical energy.