Question

(a) Give an example of different net external forces acting on the same system to produce different accelerations.

(b) Give an example of the same net external force acting on systems of different masses, producing different accelerations.
(c) What law accurately describes both effects? State it in words and as an equation.

a) Newton's First Law.
b) Newton's Second Law.
c) Newton's Third Law.
d) Law of Conservation of Energy.

Answer 1

Different net external forces on the same mass produces different accelerations; the same net external force on different masses produces different accelerations; Newton's Second Law, stated as Fnet = ma, describes these effects.

Step-by-step explanation:

Examples of Net External Forces and Accelerations

(a) An example of different net external forces acting on the same system to produce different accelerations is when two children push a wagon with a child in it versus when an adult pushes the same wagon. The adult can exert a larger force, thus creating a greater acceleration (a' > a).

(b) An example of the same net external force acting on systems of different masses to produce different accelerations can be seen when the same force is applied to two objects of differing mass; the object with the smaller mass will accelerate faster due to its lower inertia.

(c) The law that accurately describes both of these effects is Newton's Second Law of motion. In words, this law states that the acceleration of a system is directly proportional to and in the same direction as the net external force acting on the system, and inversely proportional to its mass. The equation form is Fnet = ma, where 'Fnet' is the net external force, 'm' is the mass of the system, and 'a' is the acceleration of the system.