Question

If the load on a ball bearing is reduced to half, the life of the ball bearing will

• A. Not change
• B. Increase $2$ times
• C. Increase $4$ times
• D. Increase $8$ times

Answer 1

The correct option is D Increase $8$ times

$L{P}^3=K$
$\Rightarrow L_1{P}_1^3=L_2{\left(\frac{P_1}{2}\right)}^3[P_2-\frac{P_1}{2}]$
$\Rightarrow L_2=8L_1$