What happens when a resultant force acts on a stationary and moving object?

A resultant force of 50N is applied to the right of a stationary object. This causes the object to accelerate to the right. Therefore a resultant force causes an object’s speed to change. An object is moving at a constant speed to the right. A resultant force of 50N is applied to the left. This causes the object to decelerate (slow down), therefore also causing the speed to change. A resultant force can also change the direction of speed. When an object is moving at a constant speed and a resultant force is applied to the bottom of an object, the object accelerates upwards.