When you lift an object by moving only your forearm, the main lifting muscle in your arm is the biceps. Suppose the mass of a forearm is 1.30 kg
. If the biceps is connected to the forearm a distance dbiceps
= 3.50 cm
from the elbow, how much force Fbiceps
must the biceps exert to hold a 800 g
ball at the end of the forearm at distance dball
= 34.0 cm
from the elbow, with the forearm parallel to the floor? How much force Felbow
must the elbow exert? (Figure 1)