While doing a chin-up, a man lifts his body 0.40 m. (a) How much work must theman do per kilogram of body mass? (b) The muscles involved in doing a chin-up cangenerate about 70 J of work per kilogram of muscle mass. If the man can just barely do a0.40-m chin-up, what percentage of his body's mass do these muscles constitute? (Forcomparison, the total percentage of muscle in a typical 70-kg man with 14% body fat isabout 43%.)

We are aware that when performing a chin-up, a guy raises his body 0.40 m.We need to determine how…

Answered: While doing a chin-up, a man lifts his…

Similar questions

A mountain climber is about to haul up a 90-m length of hanging rope. How much work will it take if the rope weighs 0.65 N/m? Set up the integral that gives the work done. (Type an exact answer, using radicals as needed.)
A 10 kg barbell is rolling down a hill. There is no friction or air resistance acting on it, only the force of gravity. If it starts out moving 2 ms1, and ends up moving 7 ms1, then how much work does gravity do on it?
A spring with a spring constant of 18.0 N/cm has a cage attached to its free end. (a) How much work does the spring force do on the cage when the spring is stretched from its relaxed length by 7.60 mm? (b) How much additional work is done by the spring force when the spring is stretched by an additional 7.60 mm?
Starting from rest, a 5.40-kg block slides 3.40 m down a rough 30.0° incline. The coefficient of kinetic friction between the block and the incline is µ, = 0.436. (a) Determine the work done by the force of gravity. (b) Determine the work done by the friction force between block and incline. (c) Determine the work done by the normal force. (d) Qualitatively, how would the answers change if a shorter ramp at a steeper angle were used to span the same vertical height?
You and your friend Gandalf are mowing lawns for extra spending money. Gandalf pushes his mower 25 m and applies a force of 150 N. If you apply a force of 60 N, how far must you push your mower so that the work you do equal Gandalf’s?
A 4.8 kg box has an acceleration of 1.8 m/s? when it is pulled by a horizontal force across a surface with 4, = 0.50. Find the work done over a distance of 22 cm by the following forces. (Enter your answers in joules.) (a) the horizontal force (b) the frictional force (c) the net work (d) what is the change in kinetic energy of the box?
A 58.1-kg skateboarder starts out with a speed of 2.03 m/s. He does 108 J of work on himself by pushing with his feet against the ground. In addition, friction does -243 J of work on him. In both cases, the forces doing the work are non-conservative. The final speed of the skateboarder is 7.89 m/s. (a) Calculate the change (PEf - PE0) in the gravitational potential energy. (b) How much has the vertical height of the skater changed? Give the absolute value.
The graph in the figure below shows the magnitude of the force ex- erted by a given spring as a function of the distance x the spring is stretched. How much work is needed to stretch this spring: (a) a distance of 5.0 cm, starting with it unstretched, and (b) from x - 2.0 cm to x = 7.0 cm? F (N) x (cm) 1 2 3 4 5 6 67 8 350 300 250 200 150 100 50
A person pulls a 10 kg luggage along a level road for 5 m by exerting a force of 20 N at an angle of 30° with the horizontal shoulder through a vertical distance of 1.5 m and carries it for another 5 m. How much work does he do in taking the luggage on his shoulder?