To develop muscle tone, a woman lifts a 2.50 kg weight held in her hand. She uses her biceps muscle to flex the lower arm through an angle of 60.0°. (a) What is the angular acceleration (in rad/s³) if the weight is 24.0 cm from the elbow joint, her forearm has a moment of inertia of 0.250 kg - m², and the net force she exerts is 750 N at an effective perpendicular lever arm of 1.90 cm? (Ignore gravity) rad/s (b) How much work (in J) does she do?
To develop muscle tone, a woman lifts a 2.50 kg weight held in her hand. She uses her biceps muscle to flex the lower arm through an angle of 60.0°. (a) What is the angular acceleration (in rad/s³) if the weight is 24.0 cm from the elbow joint, her forearm has a moment of inertia of 0.250 kg - m², and the net force she exerts is 750 N at an effective perpendicular lever arm of 1.90 cm? (Ignore gravity) rad/s (b) How much work (in J) does she do?
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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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Question
![### Physics Problem: Muscle Tone Development
#### Problem Statement:
To develop muscle tone, a woman lifts a **2.50 kg** weight held in her hand. She uses her biceps muscle to flex the lower arm through an angle of **60.0°**.
**(a)** What is the angular acceleration (in rad/s²) if the weight is **24.0 cm** from the elbow joint, her forearm has a moment of inertia of **0.250 kg · m²** and the net force she exerts is **750 N** at an effective perpendicular lever arm of **1.90 cm**? (Ignore gravity)
```
__________ rad/s²
```
**(b)** How much work (in J) does she do?
```
__________ J
```
#### Explanation:
In part (a), you're asked to find the angular acceleration. You can use the following formula for angular acceleration:
\[ \alpha = \frac{\tau}{I} \]
Where:
- \(\alpha\) is the angular acceleration.
- \(\tau\) is the torque applied.
- \(I\) is the moment of inertia.
Torque (\(\tau\)) can be calculated as:
\[ \tau = F \times r \]
Where:
- \(F\) is the force applied.
- \(r\) is the lever arm length.
In part (b), the work done by the muscle can be determined using the relationship between torque and rotational work:
\[ W = \tau \times \theta \]
Where:
- \(W\) is the work done.
- \(\theta\) is the angle of rotation in radians.
#### Additional Notes:
- Ensure to convert units where necessary to maintain consistency (e.g., cm to m).
- The angle in radians can be found by converting degrees to radians: \(\theta (rad) = \theta (degrees) \times \frac{\pi}{180}\).
**Note:** Graphs and diagrams are not present in the given image.](/v2/_next/image?url=https%3A%2F%2Fcontent.bartleby.com%2Fqna-images%2Fquestion%2Fdb8ba6cb-f074-43c1-b7bc-05cc004f9981%2F6ced4625-bbd8-4d6e-a0ab-006dbb6648b3%2F1m8ngzc_processed.png&w=3840&q=75)
Transcribed Image Text:### Physics Problem: Muscle Tone Development
#### Problem Statement:
To develop muscle tone, a woman lifts a **2.50 kg** weight held in her hand. She uses her biceps muscle to flex the lower arm through an angle of **60.0°**.
**(a)** What is the angular acceleration (in rad/s²) if the weight is **24.0 cm** from the elbow joint, her forearm has a moment of inertia of **0.250 kg · m²** and the net force she exerts is **750 N** at an effective perpendicular lever arm of **1.90 cm**? (Ignore gravity)
```
__________ rad/s²
```
**(b)** How much work (in J) does she do?
```
__________ J
```
#### Explanation:
In part (a), you're asked to find the angular acceleration. You can use the following formula for angular acceleration:
\[ \alpha = \frac{\tau}{I} \]
Where:
- \(\alpha\) is the angular acceleration.
- \(\tau\) is the torque applied.
- \(I\) is the moment of inertia.
Torque (\(\tau\)) can be calculated as:
\[ \tau = F \times r \]
Where:
- \(F\) is the force applied.
- \(r\) is the lever arm length.
In part (b), the work done by the muscle can be determined using the relationship between torque and rotational work:
\[ W = \tau \times \theta \]
Where:
- \(W\) is the work done.
- \(\theta\) is the angle of rotation in radians.
#### Additional Notes:
- Ensure to convert units where necessary to maintain consistency (e.g., cm to m).
- The angle in radians can be found by converting degrees to radians: \(\theta (rad) = \theta (degrees) \times \frac{\pi}{180}\).
**Note:** Graphs and diagrams are not present in the given image.
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