GATE Mechanical Engineering (ME) 2020 Shift 2 Solved Paper

A cylindrical bar with $200\mathit{m}\mathit{m}$ diameter is being turned with a tool having geometry $0^{\circ }$ $9^{\circ }-7^{\circ }-8^{\circ }-{15}^{\circ }-{30}^{\circ }-0.05$ inch (Coordinate system, ASA) resulting in a cutting force ${\mathit{F}}_{\mathit{c}1}$. If the tool geometry is changed to $0^{\circ }-9^{\circ }-7^{\circ }-8^{\circ }-{15}^{\circ }-0^{\circ }-0.05$ inch (Coordinate system, ASA) and all other parameters remain unchanged, the cutting force changes to ${\mathit{F}}_{\mathit{c}2}$. Specific cutting energy (in $\mathit{J}/{\mathit{m}\mathit{m}}^3$ ) is ${\mathit{U}}_{\mathit{c}}={\mathit{U}}_0{\left({\mathit{t}}_1\right)}^{-0.4}$, where ${\mathit{U}}_0$ is the specific energy coefficient, and ${\mathit{t}}_1$ is the uncut thickness in $\mathit{m}\mathit{m}$. The value of percentage change in cutting force $\mathit{F}\mathit{c}\mathit{z}$, i.e. $\left(\frac{{\mathit{F}}_{\mathit{c}2}-{\mathit{F}}_{\mathit{c}1}}{{\mathit{F}}_{\mathit{c}1}}\right)\times 100$, is __________(round off to one decimal place).