Answer
The disk brake system exerts the greatest torque by $33\%$ than the rim brake system.
Work Step by Step
Here we use the equation, torque $(\tau)=Fr$
Let's apply it to the rim brake system.
$\tau=Fr$ ; Let's plug known values into this equation.
$\tau=1\times10^{-3}N\times \frac{60}{2}\times10^{-2}m$
$\tau=300\space Nm$
Let's apply it to the disk brake system.
$\tau=Fr$ ; Let's plug known values into this equation.
$\tau=4\times10^{-3}N\times \frac{200}{2}\times10^{-3}m$
$\tau=400\space Nm$
Percentage of torque increment $=\frac{(400-300)}{300}\times100\%=33\%$
The disk brake system exerts the greatest torque by $33\%$ than the rim brake system.
