Question

During the sharpening of a knife with the help of a grind stone, the direction of motion of sparks is:

• A. radially outward
• B. radially inward
• C. along tangent in the direction of rotation of grind stone
• D. along tangent opposite to direction of rotation of grind stone

Answer 1

The correct option is C along tangent in the direction of rotation of grind stone

The direction of the spark is along the tangent and in the direction of the rotation. This is because friction acted on the knife is along the tangent and in direction opposite to the rotation.