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andrew-mc [135]
2 years ago
6

A weightlifter takes 0.5s to raise a barbell with 2 free-weights from the ground to a height of 0.9m. If each free-weight has a

mass of 30kg and the barbell has a mass of 20kg, calculate how much power the weightlifter produces when lifting the barbell?​
Physics
1 answer:
Anna [14]2 years ago
5 0

Answer:

P = 1412.82 [Watt]

Explanation:

First we must calculate the total mass that makes up the barbell and the two free weights at each end of the barbell.

m=30+30+20\\m= 80 [kg]

Weight is now defined as the product of mass by gravitational acceleration.

w=m*g

where:

m = mass = 80 [kg]

g = gravity acceleration = 9.81 [m/s²]

w=80*9.81\\w=784.8[N]

Now using the product of the weight by the distance traveled we can calculate the work.

W=w*d

where:

W = work [J]

w = weight = 784.8 [N]

d = distance = 0.9 [m]

W=784.8*0.9\\W=706.41[J]

And power is defined as the relationship of work at a certain time. The potency is expressed by means of the following formula.

P=W/t\\P=706.41/0.5\\P=1412.82[W]

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