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How does the mass of an object affect its momentum?

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A diagram with labeled vector illustrations. Panel A shows vector addition with two green arrows A and B forming a parallelogram, and their sum C as a red diagonal. Panel B shows vector subtraction, with A and negative B forming resultant D. Panel C demonstrates vector components using angles and projections. Panel D uses the right-hand rule with thumbs to show the direction of the cross product E = A x B and its opposite, -E = B x A. — mechanics Figure 1: (A) The vector sum C = A + B = B + A. (B) The vector difference A + (−B) = A − B = D. (C, left) A cos θ is the component of A along B and (right) B cos θ is the component of B along A. (D, left) The right-hand rule used to find the direction of E = A × B and (right) the right-hand rule used to find the direction of −E = B × A.

In physics, the momentum of an object is defined as the product of its mass and its velocity.12

Because momentum is directly proportional to mass, an increase in an object's mass results in a proportional increase in its momentum, provided the velocity remains constant. Essentially, mass acts as a measure of an object's inertia—its resistance to changes in motion—and this property directly scales the magnitude of the object's momentum.32

Mathematically, if $p$ represents momentum, $m$ represents mass, and $v$ represents velocity, the relationship is expressed as:

$p = m v$

As a vector quantity, momentum possesses both magnitude and direction. Consequently, a heavier object moving at the same velocity as a lighter one will possess greater momentum, requiring a larger force or a longer duration of force application to change its state of motion.12