Question

Scissors and shears are levers of the first order. However, the cutting edge of scissors used for cutting cloth is much longer than the cutting edge of shears used for cutting metals. Explain the difference. 

Answer 1

To increase the load arm the blades of scissor are longer so that blades move over longer when the effort arm is moved a little. 

The effort arms of shears made longer as compared to blades so that it becomes force multiplier and helps in cutting the metal sheet.