Question

If the horse power of a shaft subjected to torque alone is doubled, horse power can be increased
1. 8 times
2. 4 times
3. 16 times
4. 2 times

Answer 1

Correct Answer - Option 4 : 2 times

Concept:

Power is given by;

\(% MathType!Translator!2!1!AMS LaTeX.tdl!AMSLaTeX! % MathType!MTEF!2!1!+- % feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaaeaaaaaaaaa8 % qacaWGqbGaeyypa0ZaaSaaa8aabaWdbiaaikdacqaHapaCcaWGobGa % amivaaWdaeaapeGaaGOnaiaaicdaaaaaaa!3DDF! P = \frac{{2π NT}}{{60}}\)\(P = \frac{{2\pi NT}}{{60}}\)

Where P is in watt

N = Angular velocity

T = Torque

Calculation:

Given,

T' = 2T

\(P \propto T\)

\(\frac{{P'}}{P} = \frac{{T'}}{T} = \frac{{2T}}{T}\) ⇒ P' = 2P

So, If the horse power of a shaft subjected to torque alone is doubled, horse power can be increased 2 times.