Figure 9-51 shows a pair of forceps used to hold a thin plastic rod firmly. If each finger squeezes with a force FT = FB = 6.0 N, what force does each forceps jaw exert on the plastic rod?
Here's the picture: http://www.webassign.net/giancoli/9-51fig.gif
Thanks!
Here's the picture: http://www.webassign.net/giancoli/9-51fig.gif
Thanks!
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the trick to this question is to use torque and NOT double the forces because remeber if was a wall instead of onoe of your fingers sqeezing and moving a forcep jaw it would exert the same force as your finger does.
you have to convert the 6N into a torque we'll call it T, that T = 6*8.5 (units dont really matter because i will be cancelling them out in a sec so no need to convert to meters)
T=51Ncm
the torque exerted on the ball will be the same BUT the force will be different because its a smaller distance
SO since T=force*distanceFromPivot
T=51=ForceOnTheRod*2.7
ForceOnTheRod = 51/2.7 = 18.89N
you have to convert the 6N into a torque we'll call it T, that T = 6*8.5 (units dont really matter because i will be cancelling them out in a sec so no need to convert to meters)
T=51Ncm
the torque exerted on the ball will be the same BUT the force will be different because its a smaller distance
SO since T=force*distanceFromPivot
T=51=ForceOnTheRod*2.7
ForceOnTheRod = 51/2.7 = 18.89N