a standard man intending to do reverse curls in a gym. He holds his arms straight, using an overhand grip to hold the bar. If the mass of the bar is given as 140 kg, what is the tension in each of his shoulders? Consider the weight of the arm and the weight of the bar. Note: Use 4.9kg as the mass of the arm of the standard man.
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To find the tension in each of the man's shoulders while doing reverse curls, we need to consider the weight of the arm and the weight of the bar.
First, let's calculate the weight of the arm. The mass of the arm is given as 4.9 kg, and we can use the acceleration due to gravity, which is approximately 9.8 m/s^2, to find the weight. Weight is equal to mass multiplied by the acceleration due to gravity, so the weight of the arm is:
Weight of the arm = mass of the arm × acceleration due to gravity
Weight of the arm = 4.9 kg × 9.8 m/s^2
Weight of the arm = 47.86 N
Next, let's calculate the weight of the bar, which is given as 140 kg. Again, using the same formula:
Weight of the bar = mass of the bar × acceleration due to gravity
Weight of the bar = 140 kg × 9.8 m/s^2
Weight of the bar = 1372 N
Now, let's consider the tension in each of the man's shoulders. When the man holds his arms straight, the tension in his shoulders should be equal to the combined weight of his arm and the bar. Therefore, the tension in each shoulder is:
Tension in each shoulder = Weight of the arm + Weight of the bar
Tension in each shoulder = 47.86 N + 1372 N
Tension in each shoulder = 1420.86 N
Therefore, the tension in each of the man's shoulders while doing reverse curls is approximately 1420.86 N.