Find the force applied to you by the rubber bands?

AI Thread Summary
To find the force applied by the rubber bands during the launch, the net force must be calculated using F = ma, where the acceleration is 15 m/s² and the mass is 70 kg, resulting in a net force of 1050 N. However, this net force does not account for the gravitational force acting downward, which must be considered. The gravitational force can be calculated as F_gravity = mg, equating to 686 N for a 70 kg mass. The total force exerted by the rubber bands must overcome both gravity and provide the net upward force, leading to the equation F_rubber = F_net + F_gravity. The final force applied by the rubber bands is 1736 N.
Max CR
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Homework Statement



A giant rubber band is going to launch you straight upwards. Upon launch your acceleration is 15 m/s^2 upwards. If your mass is 70 kg, find the force applied to you by the rubber bands.

This is a copy word from word of the problem. Please be specific. I have a physics test tomorrow.

Thanks!


Homework Equations





The Attempt at a Solution



a = 15 m/s^2
M = 70 kg
F = ?

F = ma
F = (70 kg)(15 m/s^2) = 1050 N
 
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Max CR said:
F = ma
F = (70 kg)(15 m/s^2) = 1050 N
That's the net force on you during the acceleration, not the force from the rubber band.

Draw a free body diagram of you. What forces are acting? Which way do they act?
 
I do not know. I am looking but can't figure it out.
 
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