final Flashcards
a small mass hanging by a string is swung in a vertical circle in what direction is the acceleration in what direction is the net force what provides the centripetal force where is the tension in the string the greatest and the least, draw fbd in notability
acceleration is towards center of circle, net force is the same as teh acceleration bc centripetal, the gravity and teh tension provide the centripetal force in varying proportions, teh tension is teh greatest at teh btotom because it has to counteract and be greater than the friction and gravity in order to act as a centripetal force and keep it moving in a circle, and least at the top becuase gravity has weight and the force is helping it no need to coutneract it, at the top its t-mg at the bottom its t+mg
discuss two ways of recording time for objects undergoing circular motion, include units for each and relationship between them
period whihc is the time for one revolution unit is T and measured in seconds, frequency is hte amount of revolutions in one specific time frame unit is f measures in hertz, there are reciprocals of each others
a bowling ball rolls off edge of table and falls horizonatally what is the component of v
it stays the same
an object moves as projectile through airs and falls back to ground what happens to speed
steadily increases
if canoonball is fired with a mass and an angle of 35 degrees horizonatally if indetical ball is fired with same velocity was angle will it produce at teh same range
55
a football is kicked into air at 45 degress it rises and fallls what happens to acceleration
it is entirely vertical
a projectile is launces at an angle at its max height of its trajectory wht is v and a
neither velocity or acceleration is zero
a box being pusshed across the floor slows and stopped is it at equlibrium
yes when teh box stops no toher systems or net forces are acting on it besdues gravity and the normal force which are in teh same system teh box,
write an action reaction pair for when a man is pushing a box and then stops
the man pushes or exerts a froce on teh box, the box exerts an equal in magnitude and opposite direction force on man not at equlibriu bc there are 2 systems the man adn teh box so the man acts on teh box teh box acts on man
give an examples of one of newtons laws fbd in notability
the box will remain at rest until the mans feoces acts on it and accelertes it this is newtons first law
a stone droped from a cliff, an identical stone is thrown horixonatally from the same heigh compare times of the fall and landing sppeeds of te stones
stones will fall for the same trime bc vertical acceleration acting on them is constant, the stone thrown horizonatally will hae greater landing speed than stone dropped from top of cliff bc the stone thrown horixontally add both the vertical and horxinatal verlocity to get teh total velocity, the dropped stone however has no horzionatal velocity so total velocituu is equal to its vertical velocity
a ball rolls along flat table top and then rolls off edge it is falling to the floor as a projectile compare vertical distan falling in tehfirst half of the flight adn the vertical distacne falling during the second half of the flight compare the horizonatal distance during the first and second halfs of the flgiht
vertical distance the ball falls incease as time goes on so bal falls 1 meter vertical in 1 sec,andn in 2 secs it will fall 4 meters vertically bc t he acceleration is -9.8 m/s^2;… the horizontal distance during teh first half is euqal to the second hal bc the horizontal motion is constant and there is no acceleration so ball travels 1 meters horixonatally in 1 sec in 2 secs it will travel another 1 meter and so on horizontally, the horizontal component is the same throughout
can an object have varying velocity if its speed is constant
yes bc the speed and the displacen=ment can ermain constant u the direction varies, for example a car going at exactly 50 mpers turns right then left the velocity is chnging bc it is a vector while the speed which is scalar remains cosntant
what is acceleration
the rate of change in velocity, ei a car speeding up slowing down turning wheter or bnot at constant velocity jsut as long as it is turning bc it is a vector
