Question

Assertion (a): for a negative rake tool, the specific cutting pressure is smaller than for a positive rake tool under otherwise identical conditions. Reason (r): the shear strain undergone by the chip in the case of negative rake tool is larger

Answer 1

Answer: A is false but R is true, an ESE question

Explanation: since it is mentioned that it is a negative rake tool then it has more cutting force than positive rake tool and for this specific cutting pressure will be more than positive rake tool as specific cutting pressure is (cutting force/cross-section area of undeformed chip). So the Assertion given is false.

Also the shear strain will be more in negative because as for negative rake more will be cutting force so more will be pushing by cheap towards workpiece the so more will be shearing failure at the shear zone that's will result more shear strain. That's mean the Reason is true.