Both make hypotheses.

Philosophers try to use deductive and inductive reasoning to prove their hypotheses. A practice that frequently leads to erroneous conclusions.

Physicists use measurements of length, time and mass, which thusly turn experiments and observations into numbers, which can then be analyzed using Math. In other words, they use actual experience to prove their hypotheses true or false.

As simple as this idea sounds, it actually had to be invented, by a guy named Galileo in the late 1500's, in fact. Using measurements of only length and time, (the concept of mass hadn't been developed yet), he rather easily proved false several notions that had been accepted as fact for nearly two thousand years, and started the scientific odyssey we all currently enjoy. Well, it wasn't all that easy. He had to design his own unit of measurements of both length and time, then he had to invent some math with which to analyze his experiments. His successor, Isaac Newton, accelerated this development by inventing not only mass, but calculus, both of which are essential to the development of physics.

Consequently, although the physics concepts you will learn in physics are handy things to know, learning to make careful observations, measure concise data, and analyze it correctly is what the study of physics is truly all about.

Physics is like Karate?

In Karate, one studies how to defend oneself if attack, skills that are seldom used. Fringe benefits of fitness, quicker reflexes, self confidence , mental and emotional serenity, are used daily and extremely beneficial .

In physics one studies the concepts of matter and energy, techniques of experimentation, and mathematical analysis, most of which is seldom used in daily life. Fringe benefits of problem solving skills, observation, working with others, technical writing, time management skills, all are used frequently, and opportunities to develop them are found almost nowhere else in undergraduate studies.