8.1- FORCE AND ACCELERATION Flashcards
What is the push opposed by when pushing a heavy crate across a rough concrete floor?
opposed by friction
What stops the crate from moving when you stop pushing it?
friciton
What allows motion to be observed in the absence of friction?
air track
What is Newton’s first law of motion?
object either stays at rest or moves with constant velocity unless acted on by a force
How can you test how velocity of object changes if acted on by constant force?
using dynamic trolley + motion sensor connected to computer
What is the computer used to do when investigating how velocity of object changes if acted on by constant force?
used to process signal from motion sensor + to display graph showing how velocity of trolley changes with time
investigating how velocity of object changes if acted on by constant force: how is the trolley pulled?
pulled along a slopping runway using one/more elastic bands stretched to same length
investigating how velocity of object changes if acted on by constant force: why is the runway slightly sloped?
to compensate for friction
investigating how velocity of object changes if acted on by constant force: how do you test if the slope is correct?
trolley should move down runway at constant speed after being given brief push
investigating how velocity of object changes if acted on by constant force: as the trolley is pulled with a constant force, what should the velocity-time graph show?
velocity increases at constant rate
investigating how velocity of object changes if acted on by constant force: as the velocity of the trolley increases at a constant rate, what does this mean for the accelearation?
acceleration of trolley constant + can be measured by velocity-time graph
What is force proportional to?
mass * acceleration
What is the equation F=ma known as?
Newton’s second law for constant mass
What is g?
acceleration of falling object acted on by gravity only
What is the equation for weight?
W = mg
