The question asks for the term defined as the force that acts upon a mass of 1 kg, producing an acceleration of 1 m/s² in the direction it acts.

Newton Definition Explained

This definition directly corresponds to the SI unit of force, which is the Newton. It is derived from Newton's Second Law of Motion.

Newton's Second Law and Force Unit

Newton's Second Law of Motion states that the acceleration ($a$) of an object is directly proportional to the net force ($F$) acting on it and inversely proportional to its mass ($m$). The formula is:

$F = m \times a$

By definition, 1 Newton (N) is the force required to accelerate a mass of 1 kilogram (kg) at a rate of 1 meter per second squared (m/s²). Therefore, the force described in the question is 1 N:

$1 \, \text{N} = 1 \, \text{kg} \times 1 \, \text{m/s}^2$

The term that fits this definition is Newton.

Analysis of Other Options

Let's examine why the other options are incorrect:

• Density: Density is defined as mass per unit volume ($\rho = m/V$). It measures how tightly matter is packed together. It does not represent a force.
• Poise: The Poise (P) is the unit of dynamic viscosity in the CGS system. It measures a fluid's internal resistance to flow. It is not a unit of force.
• Ohm: The Ohm ($\Omega$) is the SI unit of electrical resistance. It measures how difficult it is for electric current to pass through a conductor. It is unrelated to mechanical force.

Conclusion

Based on the definition provided and the principles of physics, specifically Newton's Second Law, the correct unit of force described is the Newton.