Chapter 10, Problem 3STP

To determine

To Choose: The correct option.

Answer to Problem 3STP

Option B: 45 percent

Explanation of Solution

Given:

Mass of the box, $m=100\text{kg}$

Efficiency of ramp, $50\%=0.5$

Efficiency of pulley, $90\%=0.9$

Formula Used:

Overall efficiency of a compound machine can be obtained by calculating the product of efficiency of individual machine.

  $e=e_1\times e_2$

Calculations:

The efficiency of the compound machine is:

  $\begin{array}{c}e=e_1\times e_2\\ =0.5\times 0.9\\ =0.45\end{array}$

  $e\left(\%\right)=45\%$

Conclusion:

Thus, correct option is B.