Question

A wheel has moment of inertia 5 x 10 ^-3 kg m
and is making 20 rev/sec. The torque needed to
stop iVin 10 sec is ............. x 10-2 N-m :-
(1721 (2) 2.5 (3) 41 (4) 4.57​

Answer 1

$\huge\underline\orange{Answer}$

$\large{\boxed{{\tau = 6.28×{10}^{-2}N-m}}}$

$\huge\underline\orange{Solution}$

Given :-

$\large{I=5×{10}^{-3}}$

No. of Rev/sec (v)= 20

Time (t) = 10 s

Angular Velocity :-

$\large{{\omega = 2πv}}$

$\large{{\omega = 2π×20}}$

$\large{\boxed{{\omega = 40πrad/s}}}$

Angular Acceleration :-

$\large{\boxed{{\alpha={\frac{\omega}{t}}}}}$

$\large{{\alpha ={\frac{40π}{10}}}}$

$\large{\boxed{{\alpha = 4π rad/{s}^{2}}}}$

Torque :-

$\large{\boxed{{\tau = I{\alpha}}}}$

$\large{{\tau = 5×{10}^{-3}×4π}}$

$\large{{\tau = 62.3×{10}^{-3}}}$

$\large\blue{\boxed{{\tau=6.23×{10}^{-2}N-m}}}$

✨⛄⛄⛄✨

Answer 2

$\huge\boxed{\fcolorbox{white}{red}{Answer:-}}$

______

$\huge\underline\pink{\sf Given:-}$

➡I = 5 x 10^-3

➡No. of revolutions(v) = 20

➡Time =20s

$\huge\underline\pink{\sf Find:-}$

➡Torque=❓

$\huge\underline\pink{\sf Solution:-}$

❇ Angular velocity (ω)= 2πv

➡ω = 2π x 20 = 40π rad/s

❇Angular acceleration (α)=ω/t

➡α= ω/t = 40π/ t =40π/10=4π rad/s^2

Now,

❇Torque(τ) = I x α

➡ τ = 5 x 10^-3 x 4π

➡ τ = 6.23 x 10^-3

;)