A 4kg eagle picks up a 75g snake and raises it 2.5 m from the ground to a branch. What is the work done to raise the bird's own center of mass to the branch? (Assume g = 10 m/s2)
Correct answer: A. 100J
- A. 100J
- B. 1.875J
- C. 18.75J
- D. 187.5J
Explanation
To find the work done to raise the bird's own center of mass to the branch, we need to use the formula: Work = force x distance x cos(theta)where force is the weight of the eagle and the snake combined, distance is the vertical distance they are raised, and theta is the angle between the force vector and the displacement vector (which is 0 degrees since they are moving vertically). First, we need to find the total weight of the eagle and the snake: Total weight = weight of eagle + weight of the snake Total weight = (4 kg)(9.81 m/s2) + (0.075 kg)(9.81 m/s2) Total weight = 39.26 N + 0.74 N Total weight = 40 N Now we can calculate the work done: Work = force x distance x cos(theta) Work = (40 N)(2.5 m)(cos 0) Work = 100 J Therefore, the work done to raise the bird's own center of mass to the branch is 100 J. Mathematically other options are incorrect.
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