Question | Answer |
can friction do work on an object? | yes |
thermal energy | total energy of the moving particles in a substance |
kinetic friction | energy removed from a moving object by the object it is moving against, two objects must interact, energy in the form of heat |
static friction | friction between two objects that are not moving, prevents an object from moving, not a force but a threshold |
mechanical advantage | doing more work with less effort |
machine | a simple system that reduces the force needed to do work, increases the amount of force applied |
increasing the force | work stays the same but force is increased |
increasing the distance | the object gains potential energy |
changing the direction | force applied in the same direction as load |
input and output | two forces involved when a machine does work |
input force | (Fin) force exerted on the machine |
output force | (Fout) force exerted by the machine |
examples of an incline plane | slide, ramp |
examples of a lever | hammer, teeter totter, shovel |
examples of a wheel and axle | roller blades, door handle, wheel barrow |
examples of a pulley | well, flag, elevator, crane |
examples of a screw | light bulb, jar lid |
examples of a wedge | fork, door step, axe |