Is it good to wear a pad for 5 hours?

This really depends on how heavy your flow is in your cycle. If you are comfortable wearing the same sanitary pad for five hours, there is no downside. It is, however, best to keep changing as per your body's requirements. During heavy flow days, or if your periods are generally very heavy in flow, you may require heavy duty napkins with extra absorption to be able to keep them on for five hours or more a day.