Newton's Second Law of Motion

So this week we did a lab regarding Newton's Second Law of Motion, which states that the acceleration of an object is directly proportional to the force (or net force) on an object. However, the acceleration of an object is an inverse of the mass. The lab we did proved that when we did separate trials of differing mass on the cart vs the hanging mass. The changing force had a direct relationship, while the changing mass had an inverse relationship. So today's post has a picture of my dog, who is proving this rule with the force of touch on her and the acceleration of the wagging of her tail. The more *and harder* you push her or pet her, the more her tail accelerates. She's very light, with little mass, so it's easier for her to accelerate in comparison to a larger, thicker dog.