IB physics SL option B: engineering

torque

force that makes an object move and rotate

moment of inertia

ability of body to resist change in rotational motion

what does moment of inertia depend on

mass and how far mass mas is distributed from center of rotation

which is faster hollow or solid disk of same radius and mass

solid disk will accelerate faster because its mass is distributed closer to the center of rotation, hollow disk has more moment of inertia since mass is further away

object equillibrium

rest or constant velocity

translational equilibrium

no resultant force, net force = 0, object at rest or constant linear velocity

rotational equilibrium

no resultant torque, net torque = 0, object at rest or constant angular velocity

1st law of thermodynamics

total energy isloated in a system is constant, energy can be transfered from other forms to another but not destroyed

heat = increase in internal energy + external work done by system

isothermal

constant T, U = 0, Q=W

isovolumetric

constant V, W= 0, Q= change in U

isobaric

constant P, Q = change in U + W

adibatic

No thermal E exchanged with surroundings, change in U = -W

work in thermodynamics

PV

entropy

disorder of a system, number of states a system can have. more entropy = more states

second law of thermodynamics

in a cylic process entropy will either increase or remain the same

heat engine

something that converts heat energy into mechenical energy