Answer to Question #309255 in Physics for jazz

Question

A 5.0 kg box is being dragged with a rope. Find the magnitude of the tension necessary to keep the box moving at a constant velocity.

Answer 1

The Newton's second law says

$$ma=F_{net}=T-mg$$

When the box moves with constant velocity the acceleration is zero. So

$$T=mg\\ =5.0*9.8=49\:\rm N$$