Calculating Torque on a Diving Board: Help and Solutions

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To calculate the torque on a diving board from a 70kg person positioned 3.0m away from the front support, the gravitational force is first determined as 686.7N. The torque is then calculated using the formula τ = F * d, resulting in a torque of 2060.1Nm. The initial calculations involved setting the sum of torques to zero but led to confusion regarding the mass on F1. Ultimately, the correct torque value aligns with the expected answer of 2.1 x 10^3 m*N. Clarification on the torque calculation process was provided, resolving the initial confusion.
Drakon25th
Hello,
Alright, this is the problem:
Calculate the torque about the front support of a diving board exerted by a 70kg person 3.0m from that support
here's the picture:

________________person
|<-1.0m->|<--3.0m-->:

^ ^ ^
| | |
F1 F2 CG
Alright this is what i have done so far:

\sum T = 0

\sum T = m*g*d_F1-F2 - m_p *g*d_F2-person = 0

\sum T = m*g* 1.0m - 70.kg * g *3.0m = 0

m*g*1.0m = 70.kg*g*3.0m

m = (70.kg*g*3.0m)/(g*1.0m)

m = 210kg

I know the answer is supposed to be 2.1 x 10^3 m*N, but i don't know what to do after finding the mass on F1; can someone help me?
 
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Originally posted by Drakon25th
Calculate the torque about the front support of a diving board exerted by a 70kg person 3.0m from that support

force from gravity:
70 * 9.81 = 686.7N

torque:
686.7 * 3 = 2060.1Nm
 
ooh i see, thank you :smile:
 
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