A person falls flat on their back on some slippery ice and is unconscious for a second. The horizontal position of their legs torso and head from their feet is given by 0.45 m, 0.92 m and 1.75 m respectively and their weights are 30 kg 50 kg and 10 kg. They try to sit up on the ice which is so slippery they are not able to move their horizontal centre of mass. The new positions of their legs, torso and head from their feet are 0.25 m, 0.59 m and 0.7 m. What is the magnitude of the change in position of the person's feet

Question

A person falls flat on their back on some slippery ice and is unconscious for a second. The horizontal position of their legs torso and head from their feet is given by 0.45 m, 0.92 m and 1.75 m respectively and their weights are 30 kg 50 kg and 10 kg. They try to sit up on the ice which is so slippery they are not able to move their horizontal centre of mass. The new positions of their legs, torso and head from their feet are 0.25 m, 0.59 m and 0.7 m. What is the magnitude of the change in position of the person's feet

Answer 1

To find the magnitude of the change in position of the person's feet, we need to calculate the initial position and final position of the person's feet.

Given:
Initial position:
Legs from feet = 0.45 m
Torso from feet = 0.92 m
Head from feet = 1.75 m

Final position:
Legs from feet = 0.25 m
Torso from feet = 0.59 m
Head from feet = 0.7 m

To find the position of the feet, we need to subtract the initial position of each body part from the final position. Let's calculate:

Change in position of legs:
Initial position of legs = 0.45 m
Final position of legs = 0.25 m
Change in position of legs = Final position - Initial position = 0.25 m - 0.45 m = -0.20 m

Change in position of torso:
Initial position of torso = 0.92 m
Final position of torso = 0.59 m
Change in position of torso = Final position - Initial position = 0.59 m - 0.92 m = -0.33 m

Change in position of head:
Initial position of head = 1.75 m
Final position of head = 0.70 m
Change in position of head = Final position - Initial position = 0.70 m - 1.75 m = -1.05 m

Since the question asks for the magnitude of the change in position of the person's feet, we only consider the absolute values of the changes in positions:

Magnitude of change in position of legs = |-0.20 m| = 0.20 m
Magnitude of change in position of torso = |-0.33 m| = 0.33 m
Magnitude of change in position of head = |-1.05 m| = 1.05 m

To find the magnitude of the change in position of the person's feet, we sum up the magnitudes of the changes in position of the legs, torso, and head:

Magnitude of change in position of feet = Magnitude of change in position of legs + Magnitude of change in position of torso + Magnitude of change in position of head

Magnitude of change in position of feet = 0.20 m + 0.33 m + 1.05 m = 1.58 m

Therefore, the magnitude of the change in position of the person's feet is 1.58 meters.