Question

Biological muscle cells can be thought of as nanomotors that use the chemical energy of ATP to produce mechanical work. Measurements show that the active proteins within a muscle cell (such as myosin and actin) can produce a force of about 8.0 pN and displacements of 8.0 nm. How much work is done by such proteins?

Answer 1

Answer:

The answer is 6.4 × $10^{-20}$ Joules

Explanation:

This question wants to effectively test your knowledge of the names of the negative powers of 10, so first of all, before calculating, let me explain what each of the symbols in the units given in the question means:

Force = 8.0 pN = 8.0 × $10^{-12}$ N

displacement = 8.0 nm = 8.0 × $10^{-9}$ N

Now let us calculate the work.

work = Force × Displacement

work = 8.0 × $10^{-12}$  × 8.0 × $10^{-9}$ = 64 × $10^{-21}$

= 6.4 × $10^{20}$ Joules (in standard form)