Question

Unit 29: Prelecture/ Checkpoint/Homework/ Problems Homework: Gravitation Print Assignment View 100% until Sunday, November 24 at 11.59 PM Deadline: Standard Exercise Standard Exercise Optional Problem 3 Standard Exercise Problem 1 1 2 In 1994, the performer Rod Stewart drew over 3.0 million people to a concert in Rio de Janeiro, Brazil. The people in the group had an average mass of 80 kg. Standard Exercise Problem 3 Standard Exercise Problem 4 What collective gravitational force would the group have on a 5.5-kg eagle soaring 270 m above the throng? If you treat the group as a point object, you will get an upper limit for the gravitational force. (Express your ans wer to two significant figures.) Standard Exercise Problem 5 Standard Exercise Problem 10 N Submit You currently have 0 submissions for this question. Only 10 submission are allowed. You can make 10 more submissions for this question. 2What is the ratio of that force of attraction to the force between Earth and the eagle? (Express your answer to two significant figures.) Submit You currently have 0 submissions for this question. Only 10 submission are allowed. You can make 10 more submissions for this question.

Please help me! I've done it several times and it doesn't work out, and I only have 2 attempts. Write the answer as I should put it on the computer please. Thanks a lot

Answer 1

1) number of people, n = 3,000,000

Average mass of each person, m_av = 80 kg

total mass of people, M = 80*3000000 = 240,000,000 kg = 2.4*10⁸ kg

mass of eagle, m = 5.5 kg

distance between people and eagle,R = 270 m

Gravitational force, F = GMm/R² = 6.67*10^-11*2.4*10⁸*5.5/270²

F = 1.207*10^-6 N

2) Force between the Earth and Eagle,

F_g = mg = 5.5*9.81 = 53.95 N

Ratio, F/F_g = 1.207*10^-6 /53.95 = 2.23*10^-8