Theme A - A.1, A.2, 2.3 - Mechanics Flashcards
What are vectors and scalars?
Vectors have magnitude and direction while scalars only have magnitude.
Ax(horisontal component)=? Ay(vertical component)=?
Ax = Acos θ, Ay=Asin θ
What is a force?
An interaction between bodies that can change motion or change shape and size of a body.
What is the concept of the field used to explain?
Non-contact forces.
What is gravitational force?
All bodies with mass exert a force on other bodies. This is gravitational force.
What is weight?
The pull of gravity on a body.
What is the normal force?
The force that acts on a body that is perpendicular to the surface in contact with the body. I
What is the frictional force?
A force between two surface when in contact. It opposes motion.
What are the two types of friction?
Static, which acts on bodies at rest, and dynamic, which acts on bodies in motion.
What is tension?
The force experienced by a rope (or wire, etc.) attached to a fixed point when the rope is pulled from the other end, or the force experienced by a rope when it is pulled from both ends. Usually, an opposition to forces in one direction
What is hooke’s law?
The restoring force acting to return a spring to its original length is proportional to the extension of the spring.
What is viscous drag force?
The resistive force opposition motion in a fluid. It depends on the viscosity of the fluid.
What is viscosity?
Describes the fluids resistance to flow
What is buoyancy(upthrust)?
The force exerted by a fluid on an object partly or wholly immersed in the fluid that counteracts the weight of the body.
What causes buoyancy?
The difference in pressure between the top and bottom of the body.
What is the archimedes principle?
The buoyancy experienced by a body immersed in a fluid is equal to weight of fluid displaced.
What is Newton’s first law?
A body that experiences zero resultant force wil remain at rest or continue to move at a constant velocity. It is said to be in equilibrium.
What is inertia?
The tendency of bodies to keep their orignal state.
What is Newton’s second law?
The resultant force is the rate of change of momentum.
What is Newton’s third law?
Every action has an equal and opposite reaction. The forces act on seperate bodies.
Steps for solving a net force problem?
- Make a diagram and choose the direction that will be taken as positive
- Make a free-body diagram
- Find the net force by looking at the free-body diagram
- Set the net force equal to ma
- Solve for what is unknown
What is momentum?
The product of mass and velocity.
What is the law of conservation of momentum?
If no resultant force is acting, the initial momentum of a system is equal to the final momentum of a system(momentum is conserved).
What is impulse?
The change in momentum. It is usually caused by collision or explosion.
How do we find the impulse on a force time graph?
It is the area under the curve.
Describe elastic collisions.
The total kinetic energy is conserved. The total kinetic energy before and after the collision remains the same.
What
