Question
6 Fill in the missing values in the table below and suggest a device in each case. Device & Efficiency in % & Input & Useful output & & 140 mathrm(~kJ) & 135 mathrm(~kJ) & 17 & & 45 mathrm(~J) & 36 & 12 mathrm(MW) &
Answer
4.3
(293 Votes)
Aria
Master · Tutor for 5 years
Answer
### \begin{array}{|c|c|c|c|}\hline\ Device\ &\ Efficiency\ in\ \%\ &\ Input\ &\ Useful\ output\ \\\hline\ Electric\ Motor\ &\ 96.43\ &\ 140\ \mathrm{~kJ}\ &\ 135\ \mathrm{~kJ}\ \\\hline\ Incandescent\ Light\ Bulb\ &\ 17\ &\ 264.71\ \mathrm{~J}\ &\ 45\ \mathrm{~J}\ \\\hline\ Gas\ Turbine\ &\ 36\ &\ 12\ \mathrm{MW}\ &\ 4.32\ \mathrm{MW}\ \\\hline\end{array}
Explanation
## Step 1: Calculate Efficiency for the First Row### Efficiency is calculated using the formula:
Given Input =
and Useful Output =
:
## Step 2: Calculate Input for the Second Row### Rearrange the efficiency formula to solve for Input:
Given Efficiency = 17% and Useful Output =
:
## Step 3: Calculate Useful Output for the Third Row### Rearrange the efficiency formula to solve for Useful Output:
Given Efficiency = 36% and Input =
:
## Step 4: Suggest Devices for Each Case### Based on the calculated efficiencies and typical device efficiencies:1. First Row: A highly efficient device such as an electric motor.2. Second Row: A low-efficiency device such as an incandescent light bulb.3. Third Row: A moderately efficient device such as a gas turbine.