Mechanics Flashcards
What do we assume about a particle?
Mass of the object is concentrated in one point and air resistance can be ignored
What do we assume about a rod?
Mass is concentrated among the line and its rigid
What do we assume about a lamina?
Mass is distributed across a flat surface
What do we assume about a uniform body?
Mass of the object is concentrated at the centre of mass
What do we assume about a light object?
It has zero mass and tension is the same at both ends of a light string
What do we assume about an inextensible string?
Acceleration is the same in objects connected by a taut inextensible string
What do we assume about a smooth surface?
Assume there is no friction between the surface and any object on it
What do we assume about a rough surface?
Objects in contact with the surface experience a frictional force
What do we assume about a smooth and light pulley?
Pulley has no mass and tension is the same on either side of the pulley
How to calculate velocity?
Displacement from starting point/ time taken
What does the gradient represent in a velocity time graph?
The acceleration
What does the area under a velocity time graph represent?
The distance travelled
What is Newton’s first law of motion?
An object at rest will stay at rest and an object moving with a constant velocity will continue to move with constant velocity unless an unbalanced force acts on the object
What is Newton’s second law of motion?
The force needed to accelerate a particle is equal to the product of the mass of the particle and the acceleration produced (F=ma)
What is the formula for weight?
Weight= mass x gravity
