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 with hand is 1.80 kg. If the biceps is connected to the forearm a distance of 2.50 cm from the elbow, what is the magnitude of the torque exerted by the biceps to hold a 44.5 N (about 10 lbs) ball at the end of the forearm at distance of 35.0 cm from the elbow, with the forearm parallel to the floor, in N·m? Use g = 10.0 m/s2.
Angular Momentum
The momentum of an object is given by multiplying its mass and velocity. Momentum is a property of any object that moves with mass. The only difference between angular momentum and linear momentum is that angular momentum deals with moving or spinning objects. A moving particle's linear momentum can be thought of as a measure of its linear motion. The force is proportional to the rate of change of linear momentum. Angular momentum is always directly proportional to mass. In rotational motion, the concept of angular momentum is often used. Since it is a conserved quantity—the total angular momentum of a closed system remains constant—it is a significant quantity in physics. To understand the concept of angular momentum first we need to understand a rigid body and its movement, a position vector that is used to specify the position of particles in space. A rigid body possesses motion it may be linear or rotational. Rotational motion plays important role in angular momentum.
Moment of a Force
The idea of moments is an important concept in physics. It arises from the fact that distance often plays an important part in the interaction of, or in determining the impact of forces on bodies. Moments are often described by their order [first, second, or higher order] based on the power to which the distance has to be raised to understand the phenomenon. Of particular note are the second-order moment of mass (Moment of Inertia) and moments of force.
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 with hand is 1.80 kg. If the biceps is connected to the forearm a distance of 2.50 cm from the elbow, what is the magnitude of the torque exerted by the biceps to hold a 44.5 N (about 10 lbs) ball at the end of the forearm at distance of 35.0 cm from the elbow, with the forearm parallel to the floor, in N·m? Use g = 10.0 m/s2.
Your answer needs to have 3 significant figures, including the negative sign in your answer if needed. Do not include the positive sign if the answer is positive. No unit is needed in your answer, it is already given in the question statement.
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