According to Newton's Second Law, if the mass of an object is doubled while keeping the force constant, what happens to its acceleration?

In the context of Newton's Second Law, which states that force equals mass times acceleration (F = ma), if the mass of an object is doubled while the applied force remains constant, the acceleration must decrease.

To understand this, rearranging the formula gives us acceleration (a) as a function of force (F) and mass (m):

a = F / m.

If you double the mass (now 2m) and keep the force (F) constant, the new equation for acceleration becomes:

a' = F / (2m).

This indicates that the new acceleration (a') is half of the original acceleration (a), because with a greater mass, the same force results in less acceleration. As a result, the acceleration is indeed halved. This principle reflects a fundamental aspect of mechanics: greater mass resists changes in motion, which is why a larger mass leads to a lower acceleration when the force is unchanged.