Question

How many slices of bread did each climber have to eat to compensate for the increase of the gravitational potential energy of the system climbers-Earth? (One piece of bread releases about 1.0×106J of energy in the body.) Assume that the height of Mt. Everest is 8850 m, the weight of a person is about 79 kg , and efficiency in converting the body's chemical energy into mechanical work is 10.5 %.

Answer 1

Answer:

So No of slices to be consumed by each person = n = 65

Explanation:

Energy released by one slice = E1

$E1=10^6\ J$

h = 8850 m ; m = 79 kg ,η= 10.5%

We know that potential energy given as

u = m g h

u = 79 x 9.81 x 8850

$u=6.8\times 10^6\ J$

we know from the defination of efficiency that,  η= E(out)/E(in)

Now amount of PE has to be compensated, In our case, E(out) =u

$0.105=\dfrac{E(out)}{E(in)}$

$0.105=\dfrac{6.8\times 10^6}{E(in)}$

$E(in)=64.76\times 10^6\ J$

Let n be the number of bread slices to be consumed.

n = E(in)/E1

$n=\dfrac{64.76\times 10^6}{10^6}$

n=64.76

So No of slices to be consumed by each person = n = 65