# physics

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Proponents of astrology claim that the positions of the planets at the time of a baby's birth will affect the life of that person in important ways. Some assert that this effect is due to gravity. Examine this claim with Newton's law of gravity. Calculate the maximum force exerted on the baby by the planet Mars and compare that with the force of gravity exerted by the mass of the doctor's head as she delivers the baby. Assume Mars is at its closest approach to Earth at the time. You will need to estimate the mass of a newborn, as well as the mass and distance between the doctor's head and the baby.

1) Determine the distance from the Earth to Mars in meters

2) Calculate the maximum force exerted on the baby by the mass of the doctor's head as she delivers the baby.

3) Calculate the maximum force exerted on the baby by the planet Mars.

• physics - ,

You have posted this once and received two responses. Posting again won't get anymore help until you've followed Bob P's advice and followed 1-6 of the instructions.

• physics - ,

i did try to but i still didn't understand it that's why i reposted it

• physics - ,

You have to make some assumptions to come up with numbers. First of all, the closest possible approach of Mars to the Earth is 35 million miles or, 5.63*10^10 meters. That is explained at
http://cseligman.com/text/planets/marsoppositions.htm

You need the mass of Mars. That is 6.42*10^23 kg.

Assume the doctor's head mass is 4 kg and the baby's mass is 4kg, and the separation of the doctor's head is 0.5 meter during delivery.

You will have to look up the value of Newton's universal gravity constant G and crank out some numbers to get the actual forces. The ratio of the doctor's head force to the Mars force will be
(4/6.42*10^23)*(5.63*10^10/0.5)^2 = 0.079

So the gravitational influence of Mars is greater than that of the doctor in this situation, but that does not prove astrology has an important influence.

• physics - ,

thank you!