A waiter holds two plates of food in one hand. His forearm has a mass of 2.8kg and the centre of mass of his forearm is located 11cm from his elbow joint. The centre of mass of the two plates is located 32cm from his elbow joint and the total mass of the two plates is 1.75kg. His bicep is attached to the bones of his forearm is 3.6cm from his elbow joint. Assume his forearm is held completely horizontal. a. What is the torque produced by the mass of the two plates? Torque = Nm b. What is the torque produced by the mass of the waiter's forearm? Torque = 0 c. What force must be exerted by the waiter's biceps muscle to ensure that the plates and forearm are motionless? Ny Force = Nm

A waiter holds two plates of food in one hand. His forearm has a mass of 2.8kg and the centre of mass of his forearm is located 11cm from his elbow joint. The centre of mass of the two plates is located 32cm from his elbow joint and the total mass of the two plates is 1.75kg. His bicep is attached to the bones of his forearm is 3.6cm from his elbow joint. Assume his forearm is held completely horizontal. a. What is the torque produced by the mass of the two plates? Torque = Nm b. What is the torque produced by the mass of the waiter's forearm? Torque = 0 c. What force must be exerted by the waiter's biceps muscle to ensure that the plates and forearm are motionless? Ny Force = Nm

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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Rotational Equilibrium And Rotational Dynamics

In physics, the state of balance between the forces and the dynamics of motion is called the equilibrium state. The balance between various forces acting on a system in a rotational motion is called rotational equilibrium or rotational dynamics.

Equilibrium of Forces

The tension created on one body during push or pull is known as force.

Question

A waiter holds two plates of food in one hand. His forearm has a mass of 2.8kg and the centre of mass of his forearm is located
11cm from his elbow joint. The centre of mass of the two plates is located 32cm from his elbow joint and the total mass of the
two plates is 1.75kg. His bicep is attached to the bones of his forearm is 3.6cm from his elbow joint. Assume his forearm is
held completely horizontal.
a. What is the torque produced by the mass of the two plates?
Torque =
Nm
b. What is the torque produced by the mass of the waiter's forearm?
Torque = Nm
c. What force must be exerted by the waiter's biceps muscle to ensure that the plates and forearm are motionless?
=ONŷ
Force =

Find the torques created by F
and about point O for the two
forces as applied in the figure to
the right, assuming
counterclockwise is positive.
Also find the net torque. Be sure
to include the appropriate sign
for all answers!
71=
N.m
72 = N.m
Net Torque =
N.m
30°
F₁ = 17 N
2.2 m
Return this question to its initial state
120°
3.3 m
F₂ = 17 N

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