Question

What is the magnitude of the force exerted by the biceps fbiceps? What is the magnitude of the force exerted by the elbow felbow?

Answer 1

Answer:

The magnitude of the force exerted by the biceps $f_b_i_c_e_p_s$ is 218.38N

The magnitude of the force exerted by the elbow $f_e_l_b_o_w$ is 194.37N

Explanation:

Firstly , lets calculate the magnitude of force exerted by biceps $f_b_i_c_e_p_s$ -

Mass of the forearm=

$m_f=1.50kg$

Mass of the ball =

$m_b_a_l_l=950g$

   = 0.950kg

so, weight of the forearm=

$w_f=m_f$ g

weight of the ball=

$w_b_a_l_l=m_b_a_l_l$ g

Now , balancing torque about the elbow , we have-

$F_b_i_c_e_p_s\times d_b_i_c_e_p_s= w_f\times\frac{d_b_a_l_l}{2} + w_b_a_l_l\times d_b_a_l_l$

(here , distance of the bicep is 2.50cm = 0.025m and distance of the ball is 36cm= 0.36m)

Now putting the given values in the formula -

$F_b_i_c_e_p_s\times 0.025= 0.95\times9.8\times\frac{0.36}{2} +1.50\times 0.36$

$F_b_i_c_e_p_s=218.38N$

Now, lets calculate the force exerted by elbow $F_e_l_b_o_w$ -

Balancing the vertical forces

$F_b_i_c_e_p_s=F_e_l_b_o_w+w_f+w_b_a_l_l$

$F_e_l_b_o_w = 218.38-(1.00\times9.8)-(0.95\times9.8)$

$F_e_l_b_o_w=194.37N$