What would happen to the the 5.98e24 kg Earth?

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Homework Statement



If 270 million people in the US jumped in the air at simultaneously, pushing off Earth with an average force of 800 N each for a time of 0.10 seconds, what would happen to the the 5.98e24 kg Earth? Show calculation that justifies your answer.

Homework Equations



F = mv/t
p = mv

The Attempt at a Solution



F = 800 N
t = 0.10 s
m = 5.98e24 kg

800 = (5.98e24 * v) / 0.10

v = 1.3378 e -23

p = 5.98e24 * 1.3378e-23
p = 80 kg*m/s
 
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Thats almost right. You forgot the 270 million bit.
 
chaoseverlasting said:
Thats almost right. You forgot the 270 million bit.

so do i just times 270 mil by 80?
 
Not quite. F=dp/dt, dp=Fdt. Total change in momentum is zero for the system, therefore,
p(e)=p(people).

This gives p(e)=(270e6)*800*0.1. From this you find the velocity of earth.