Final answer:
Increasing mass decreases acceleration when force is fixed, according to Newton's Second Law which states that acceleration is inversely proportional to mass. Experimental results should reflect this relationship, and experiments designed to test this must control mass carefully.
Step-by-step explanation:
When force is fixed, an increase in mass will decrease acceleration according to Newton's Second Law of Motion. This law states that acceleration is directly proportional to the net external force acting on a system and inversely proportional to its mass. The formula for this law is often written as F = ma, where F is the net force applied to the object, m is the mass of the object, and a is the acceleration of the object. Therefore, keeping the force constant and increasing the mass will lead to a decrease in acceleration. Your experimental results should support Newton’s second law if they show that as mass increases, acceleration decreases when force remains unchanged.
Moreover, when designing an experiment to test the relationship between force and acceleration, the independent variable would be the applied force, and the dependent variable would be the measured acceleration. Ensuring that mass is constant usually requires careful experimental design.
Lastly, in verifying whether your results make physical sense, always check that the units are consistent and that the magnitude of the results matches what would reasonably be expected in the physical situation you're examining. This is an integral part of the scientific process.