Kinematics Flashcards
Definition of displacement
Displacement of an object is the distance from a fixed point in a specific direction
Define average velocity
It is the total change in displacement over the total time taken
Define average acceleration
It is the change in velocity over the total time taken.
What does it mean when velocity and acceleration are in the same direction?
An object is speeding up
What does it mean when velocity and acceleration are in opposite directions?
The object is slowing down
What are the 3 kinematic equations?
s=ut+1/2at^2
v=u+at
v^2=u^2+2as
what are the 2 equations for horizontal motion in projectile motion?
sx=uxt
vx=ux
What is constant maximum velocity also known?
Terminal velocity
When does terminal velocity occur?
When net force on the object=0
What forces are acting on the ball when it reaches its maximum height after it is thrown vertically upwards?
Only its weight is acting.
No AR as it is momentarily at rest at maximum height.
Why does the ball has an acceleration downwards greater than 9.81ms-2 as it is being thrown upwards?
As the ball is thrown upwards, it experiences a drag force downwards due to air resistance. As both drag force and its weight is acting downwards, it results in an acceleration downwards larger than acceleration due to gravity.
Why does the ball reaches a smaller maximum height when it is thrown in the presence of air resistance?
As the ball travels up, AR cause the ball to experience a drag force downwards. As both drag force and its weight is acting downwards, it causes the ball to experience a greater resultant downward force as it ascends. The ball decelerates upwards at a higher rate and hence reaches a smaller maximum height.
Why does the horizontal distance of the projectile motion of the ball smaller in the presence of air resistace?
Since there is air resistance acting in the horizontal direction as well, the horizontal velocity is reduced and range is smaller.
Does TV occur in both liquid and gas?
Yes
