Grading Rubric - 10 points per problem 2 points for the \"Prepare\" part includi

Question

Grading Rubric - 10 points per problem 2 points for the "Prepare" part including appropriate diagrams/pictorial representation, a list of knowns, and of list of what to find. 2 points for a bulleted "Plan" with the steps you will use. 5 points for the "Solution." You MUST begin with the textbook version of any equation you use in symbolic form. All of the steps of the solution must be shown. All of the algebra must be shown. Answers must have the appropriate units. 1 point for "Assessing your answer including acknowledgement that the goal was met, the appropriate units are included, and that the answer is reasonable. #1 A helium filled balloon of total mass M is ascending vertically with an upward acceleration a. How much mass must be added to the basket of the balloon in order for it to have an downward acceleration a?

Explanation / Answer

Let:
F be the lifting force (buoyant force),
M be the mass of the balloon ascending,
m be the mass added in the basket,
a be the acceleration of the balloon,
g be the acceleration due to gravity.

Ascending : F – Mg = Ma

Descending: (M + m)g - F= (M + m)a

Adding to eliminate F: (M + m)g – Mg = 2Ma + ma
mg = (2M + m)a
m(g - a) = 2Ma
m = 2Ma / (g - a).

Related Questions

Navigate

• Browse (All)
• Browse G
• Subjects

---

---

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