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An engineer claims to have made an engin...

An engineer claims to have made an engine delivering 10 kW power with fuel consumption of `1gs^(-1)` . The calorific value of fuel is 2 k cal / g . His claim

A

valid

B

invalid

C

dependent on engine design

D

dependent on load

Text Solution

Verified by Experts

The correct Answer is:
B
(b) Given, `P_(output)=10 kW`
Now, `P_("input")=2xx10^(3)" calg"^(-1)xx1 g s^(-1)`
`=2xx10^(3)" cal s"^(-1)=2xx10^(3)xx4.2 Js^(-1)=8.4" k W"`
As, `P_("output") gt P_("input")`, hence the claim given in question is never possible.
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