Two friends, Joe and Sam, go to the gym together to strength train. They decide to start off with an exercise called flat bench press. Lying flat on a bench with their arms in an extended position, they slowly lower (to their chest) and then raise a barbell back to the starting position. They start off by using a 45.0 kg barbell. Joe is taller than Sam which means Joe\'s arms are 69.4 cm long while Sam\'s are 60.6 cm. Calculate the work done by Joe, WJoe, when he raises the barbell to finish one repetition. The acceleration due to gravity is 9.81 m/s3

Respuesta :

the accelerated gravity will cause 1/2 things to happen either

a. they'll drop it

or

b.it'll hit them in the face!!! XD

Given:
45.0 kg barbell
Joe\'s arms are 69.4 cm long while Sam\'s are 60.6 cm
acceleration due to gravity is 9.81 m/s3
Find:
Work
Solution:
F = ma
F = 45(9.81m/s2)
F = 441.45 N

W = Fd
W = (441.45 N)(0.694m)
W = 306.4 J