Question

A woman lifts a 7.2-kg barbell in each hand with her arm in a horizontal position...

A woman lifts a 7.2-kg barbell in each hand with her arm in a horizontal position at the side of her body and holds it there for 3 s. The deltoid attaches 13 cm from the shoulder joint and makes a 13∘ angle with the humerus. The barbell in her hand is 0.55 m from the shoulder joint, and the center of mass of her 4.0-kg arm is 0.24 m from the joint.

A) Determine the force that the deltoid exerts on the humerus.

B) Determine the magnitude of the force that the lifter's shoulder joint exerts on her humerus.

C) Determine the direction of the force (measured clockwise from the positive x-axis) that the lifter's shoulder joint exerts on her humerus.

I need help especially on B and C -- been stuck on B for like half an hour! Please help

Homework Answers

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
A woman lifts a 7.2-kg barbell in each hand with her arm in a horizontal position...
A woman lifts a 7.2-kg barbell in each hand with her arm in a horizontal position at the side of her body and holds it there for 3 s. The deltoid attaches 13 cm from the shoulder joint and makes a 13∘ angle with the humerus. The barbell in her hand is 0.55 m from the shoulder joint, and the center of mass of her 4.0-kg arm is 0.24 m from the joint. 1) Determine the force that the deltoid...
A woman lifts a 7.2-kg barbell in each hand with her arm in a horizontal position...
A woman lifts a 7.2-kg barbell in each hand with her arm in a horizontal position at the side of her body and holds it there for 3 s. The deltoid attaches 13 cm from the shoulder joint and makes a 13∘ angle with the humerus. The barbell in her hand is 0.55 m from the shoulder joint, and the center of mass of her 4.0-kg arm is 0.24 m from the joint. Determine the magnitude of the force that...
A50kg woman repeatedly lifts a 20kg barbell 0.80m from her chest to an extended position above...
A50kg woman repeatedly lifts a 20kg barbell 0.80m from her chest to an extended position above her head. A) if her body retains 10J of thermal energy for each joule of work done while lifting, how many times must she lift the barbell to warm her body to 0.50°C? B) state any assumptions you used C) list all of the physics ideas you used to solve this problem
A 74.0 kg weight lifter is doing arm raises using a 7.50 kg weight in her...
A 74.0 kg weight lifter is doing arm raises using a 7.50 kg weight in her hand. Her arm pivots around the elbow joint, starting 40.0 ∘ below the horizontal. (See the figure(Figure 1).) Biometric measurements have shown that both forearms and the hands together account for 5.65 % of a person's weight. Since the upper arm is held vertically, the biceps muscle always acts vertically and is attached to the bones of the forearm 5.50 cm from the elbow...
You hold a 1.80-N softball in your hand as shown in the figure. Consider your forearm...
You hold a 1.80-N softball in your hand as shown in the figure. Consider your forearm and hand to be a uniform rod with a mass of 1.85 kg and the distance between the elbow joint and the ball in your hand is 2L = 22.5 cm. Your biceps exerts an upward force of 12.0 N on the forearm and is attached at a distance of d = 2.20 cm from the elbow. (a) Using the elbow joint as the...
A) A man holds a 185-N ball in his hand, with the forearm horizontal (see the...
A) A man holds a 185-N ball in his hand, with the forearm horizontal (see the figure). He can support the ball in this position because of the flexor muscle force , which is applied perpendicular to the forearm. The forearm weighs 18.2 N and has a center of gravity as indicated. Find (a) the magnitude of and the (b) magnitude and (c) direction (as a positive angle counterclockwise from horizontal) of the force applied by the upper arm bone...
1. A person pushes on a doorknob with a force of 5.00 N perpendicular to the...
1. A person pushes on a doorknob with a force of 5.00 N perpendicular to the surface of the door. The doorknob is located 0.800 m from the axis of the hinges of the door. The door begins to rotate with an angular acceleration of 2.00 rad/s2. What is the moment of inertia of the door about hinges? Select one: a. 6.50 kg.m2 b. 2.50 kg.m2 c. 12.5 kg.m2 d. 2.00 kg.m2 2. A dumbbell has a connecting bar of...
1. Tendons and ligaments are similar because they both have: a limited blood supply and low...
1. Tendons and ligaments are similar because they both have: a limited blood supply and low metabolism an abundant blood supply and low metabolism a limited blood supply and high metabolism an abundant blood supply and high metabolism 2. What is the name of the outer layer of connective tissue on skeletal muscle? perimysium epimysium endomysium intermediate fascia 3. The functional units of skeletal muscle that allow it shorten are: tendons fascicles sarcomeres perimysium 4. In terms of muscle actions...
12. Through what angle in degrees does a 31 rpm record turn in 0.27 s 13....
12. Through what angle in degrees does a 31 rpm record turn in 0.27 s 13. Starting from rest, the same torque is applied to a solid sphere and a hollow sphere. Both spheres have the same size and mass, and both are rotating about their centers. After some time has elapsed, which sphere will be rotating faster? answer choices: a. hollow sphere b. They will be rotating equally fast c. solid sphere 14. In movies, it often happens that...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT