Suppose that a person eats a diet of 2125 Calories per day. Part A Convert this

Question

Suppose that a person eats a diet of 2125 Calories per day.

Part A

Convert this energy into J.

Express your answer using four significant figures.

SubmitMy AnswersGive Up

Part B

Convert this energy into kJ.

Express your answer using four significant figures.

SubmitMy AnswersGive Up

Part C

Convert this energy into kWh.

Express your answer using four significant figures.

SubmitMy AnswersGive Up

The gas in a piston (defined as the system) is warmed and absorbs 645 J of heat. The expansion performs 350 J of work on the surroundings.

Part D

What is the change in internal energy for the system?

SubmitMy AnswersGive Up

A system releases 400 kJ of heat and does 105 kJ of work on the surroundings.

Part E

What is the change in internal energy of the system?

SubmitMy AnswersGive Up

Suppose that a person eats a diet of 2125 Calories per day.

Part A

Convert this energy into J.

Express your answer using four significant figures.

  J  

SubmitMy AnswersGive Up

Part B

Convert this energy into kJ.

Express your answer using four significant figures.

  kJ  

SubmitMy AnswersGive Up

Part C

Convert this energy into kWh.

Express your answer using four significant figures.

  kWh  

SubmitMy AnswersGive Up

The gas in a piston (defined as the system) is warmed and absorbs 645 J of heat. The expansion performs 350 J of work on the surroundings.

Part D

What is the change in internal energy for the system?

E =   J  

SubmitMy AnswersGive Up

A system releases 400 kJ of heat and does 105 kJ of work on the surroundings.

Part E

What is the change in internal energy of the system?

E =   kJ  

SubmitMy AnswersGive Up

Explanation / Answer

(A) 1 cal = 4.18 joule

2125 cal = 8882.5 joule

up to four significant number it will be 8882 joules.

(B) 1 joule = 1/1000 Kilojoule

8882 joule = 8.882 KJ

up to four significant number will be same 8.882

(C) 1 kjoule = 2.777778 x 10-4 KW-h

8.882 KJ = 8.882 x 2.777778 x 10-4 = 2.467 x 10-3 Kw-h

(D) change in internal energy = q + w

q will be positive as heat absorbed by the system

w will be negative as work done by the system on the surrounding

= 645 - 350

= 295 joule

(e) as heat released, therefore, it will be in negative means -400 kJ and work will also be negative because done by system change in internal energy will be = q+w

= - 400 - 105

= - 505 KJ

  

Related Questions

Navigate

• Browse (All)
• Browse S
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.