Angelito wanted to lose weight by dieting and exercising. One day, he only had a loaf of bread with an energy content of 2.50 x 10^5 J for his breakfast. To exercise, he lifted a 28.34kg to a height of 0.5m. How many times must he lift and lower the barbell to burn 1.25 x 10^4 J?
how did you get 90?if you wouldn't mind me asking
90
I don't know the answer! Please help me!
NAME?
To determine how many times Angelito must lift and lower the barbell to burn 1.25 x 10^4 J, we need to calculate the energy expenditure per lift and lower motion of the barbell.
First, let's determine the energy expenditure per lift or lower motion. We can calculate this using the formula:
Energy expenditure = (Mass of the object) x (Gravitational acceleration) x (Height)
Given:
Mass of the barbell = 28.34 kg
Gravitational acceleration = 9.8 m/s^2
Height = 0.5 m
Energy expenditure per lift or lower motion = (28.34 kg) x (9.8 m/s^2) x (0.5 m)
= 138.367 J
Now, let's find how many times Angelito needs to lift and lower the barbell to burn 1.25 x 10^4 J.
Number of lifts and lowers = (Total energy to be burned) / (Energy expenditure per lift or lower motion)
Given:
Total energy to be burned = 1.25 x 10^4 J
Energy expenditure per lift or lower motion = 138.367 J
Number of lifts and lowers = (1.25 x 10^4 J) / (138.367 J)
≈ 90.24
Since Angelito cannot perform a fraction of a lift or lower, he would need to do 90 lifts and lowers to burn 1.25 x 10^4 J.