Forces In Action Flashcards
(7 cards)
What is the centre of gravity?
An imaginary point at which the entire weight of an object appears to act.
What is drag?
The resistive force of an object travelling through a fluid, the same as friction. Acts opposite to the direction of motion.
What affects drag?
Speed: Faster objects experience more drag.
Shape: Streamlined shapes have less drag.
Surface area: Larger surfaces facing the direction of movement create more drag.
Density of the fluid: Moving through water creates more drag than air because water is denser.
Cross-Sectional Area: Larger area, greater drag
What is terminal velocity?
When the drag force of an object is equal and opposite to its weight. Zero acceleration and speed is constant.
What is the moment of a force?
The turning effect of a force about some axis or point.
Defined as: Force x Perpendicular distance from the axis.
What is the principle of moments?
When a body is in equilibrium, the sum of the anticlockwise moments is equal to the sum of the clockwise moments about any axis.
What is the definition of density?
The mass per unit volume.
