Transcript 1.28.15 Terminal velocity ppt

CH 10 Section 2 Notes
Forces - Terminal Velocity
Objectives:
By the end of this presentation, you
should be able to:
• Describe and explain what is meant by
terminal velocity.
• Describe and explain how forces
change on a falling object.
Terminal Velocity
Consider a skydiver:
1) At the start of his jump the air
zero so he
resistance is _______
accelerates downwards.
2) As his speed increases his air
increase
resistance will _______
3) Eventually the air resistance will be
big enough to _______
balance the
skydiver’s weight.
At this point the forces are balanced
constant so his speed becomes ________
this is called _.
How the forces change with time.
KEY:
Weight is a constant
value and is always
present.
Air Resistance is
proportional to the
speed.
Resultant Force - the
bigger the unbalanced
force, the greater the
acceleration.
Terminal Velocity
Consider a skydiver:
4) When he opens his parachute the
increases
air resistance suddenly ________.
This causes him to start
_______________.
slowing down
5) Because he is slowing down, his air
resistance will _______
decrease until it
balances his _________.
The
weight
skydiver has now reached a new,
terminal velocity
lower ________________.
Velocity-time graph for the sky diver
Parachute opens –
diver slows down
Velocity
Speed
increases…
Terminal
velocity
reached…
Time
New, lower terminal
velocity reached
Diver hits the ground