"A particle originally at rest, or moving in a straight line with constant velocity, tends to remain in this state provided the particle is not subjected to an unbalanced force" is

• Newton's Law of Motion I

• Newton's Law of Motion II

• Newton's Law of Motion III

"A particle acted upon by an unbalanced force F experiences an acceleration a that has the same direction as the force and a magnitude that is directly proportional to the force" is

• Newton's Law of Motion I

• Newton's Law of Motion II

• Newton's Law of Motion III

According to Newton's Law of Motion III, the mutual forces of action and reaction between two particles are

• inequal

• equal

• opposite

• composite

• collinear

Basic quantities in mechanics are

• Length

• Time

• Mass

• Electric

• Health

Models or idealizations used in mechanics are

• Particle

• Ideal Body

• Rigid Body

• Concentrated Detergent

• Concentrated Force

Systems of units used both in SI and FPS

• meter

• foot

• second

• kilogram

• slug

Where s is the position in meters, m; t is time in seconds, s; v is velocity in m/s; and a is acceleration in m/s², equations below are dimensionally homogeneous, except

• s = v⋅t +½⋅a⋅t²

• a = 2⋅s⋅t² - 2⋅v/t

• s = v/t +½⋅a⋅t²

• a = 2⋅s/t² - 2⋅v/t

Three significant figures of 23400 is

• 23.4⋅10³

• 234⋅10²

• 2340⋅10¹

• 23400⋅10⁰

50 mN ⋅ 6 GN =

• 30 kN²

• 300 kN²

• 30 MN²

• 300 MN²