Question

If 150 kJ of energy is needed for muscular work to walk a distance of one km, then how much
of glucose one has to consume to walk a distance of 5 km. Provided only 30% energy is availah
for muscular work. The enthalpy of combustion of glucose is 3000 kJ mot.

Answer 1

For walking 1 km the man needs 150KJ of energy. To walk 5 kms he needs 150X5=750 KJ energy. If only 30% of energy is available for muscular work, the total energy needed will be 750/30X100= 2500KJ 1 mole of glucose produces 3000 KJ. Then for producing 2500 KJ, 5/6 mole of glucose =5/6X180 =150 gms of glucose will be needed (assuming molecular weight of glucose=180 gms)