What does a 128 N rock weigh if it is accelerating upward at 10.0 m/s^2?

What does a 128 N rock weigh if it is accelerating downward at 5.50 m/s^2?

Please explain how you come up with your answers!

Question

What does a 128 N rock weigh if it is accelerating upward at 10.0 m/s^2?

What does a 128 N rock weigh if it is accelerating downward at 5.50 m/s^2?

Please explain how you come up with your answers!

anonymous · Answer

128N is the weight. If you are talking about the rock's apparent weight due to the acceleration you need to use Newton's 2nd law. Where ma=Apparent weight - weight. Apparent weight = ma+weight. This is similar to how you feel a little heavier when an elevator moves upward. Hope this helps.

anonymous · Answer

Still haven't quite got it... The weight would change if it is accelerating wouldn't it?

anonymous · Answer

No, the weigh remains the same. Only the normal reaction force changes.