[Dynamics]

Question 1

21. Net Force

Answer 1

F NET. Resultant force. Vector sum of all forces acting on an object.

Question 2

22. Mass

Answer 2

m. Mass is both a property of a physical body and a measure of its resistance to acceleration (a change in its state of motion) when a net force is applied. An object’s mass also determines the strength of its gravitational attraction to other bodies. Measured in kilograms, kg.

Question 3

23. Newton

Answer 3

A force of one Newton will give a mass of 1 kg an acceleration of 1 ms-2 in the direction of the force. Derived SI unit for force.1N = 1kg x 1ms-2 = 1kgms-2.

Question 4

24. Weight

Answer 4

W. Gravitational force acting on an object. F = m a -> W = m g. gEARTH = 9.81 ms-2.

Question 5

25. Tension

Answer 5

T. The pulling force exerted by a string, cable or chain on an object.

Question 6

26. Normal Contact Force

Answer 6

N or R. Reaction force. The force exerted by a surface on an object, which acts perpendicular to the surface.

Question 7

27. Upthrust

Answer 7

U. The upward buoyant exerted on a body immersed in a fluid (liquid or gas).

Question 8

28. Friction

Answer 8

A drag or resistive force that opposes motion between two surfaces. Objects do not need to be moving to experience friction.

Question 9

29. Free Body Diagram

Answer 9

Diagrams used to show the relative magnitude and direction of all forces acting upon an object in a given situation, using arrows.