Warm-Up Identify the stimulus and response for Phototropism Stimulus Response - Geotropism Stimulus Response -
Warm-Up Identify the stimulus and response for Phototropism Stimulus Response - Geotropism Stimulus Response - Light or Sun Stem bends toward light (positive phototropism) Gravity Root grow down (positive) Stem grow up (negative)
Today s Task Update Journal Work Big Ideas 24 Physics Practice 25 Turn in Plant Forces Brochure/Foldable Plant Force Practice Work Big Ideas Physics Practice
Grading Utensil red/orange/pink pen or pencil Plant Forces Foldable Plant Forces Practice Everything else under the table
Work Big Ideas
Work Is done by moving an object in the direction of the force. Force Force Motion of Object
Work Examples NO Work Examples
Work Examples Raising a brick over your head Holding a brick Throwing a Frisbee to your friend Standing still Jogging a mile Trying to lift a box, but can t NO Work Examples
Calculating Work Work = (force)(distance) F W D Work = Force X Distance Force = Work Distance = Work Distance Force
A force of 2.5 N is needed to push a wheelbarrow loaded with a sack of potatoes. How much work must be done to push the wheelbarrow 60 meters?
A force of 2.5 N is needed to push a wheelbarrow loaded with a sack of potatoes. How much work must be done to push the wheelbarrow 60 meters? W=F x D W= 2.5N x 60m W = 150 Nm or Joules
Simple Machines Decrease amount of force needed Increase the distance traveled Pulleys change direction of force Same amount of work Examples Inclined plane (ramp) Pulley (fixed, movable) Lever (3 classes, depends on where fulcrum located) Wheel & Axle, Wedge, Screw,
The box is lifted to the same height in all three scenarios. WORK = Force x Distance Scenario A The box is lifted straight up without a ramp a distance of 2 meters, which requires a force of 10 newtons; 10N X 2m = 20 joules Scenario B A ramp is used to raise the box, the ramp cause the box to be carried a farther distance (5m), however it also requires less force (4N) 4N X 5m = 20 joules of work Scenario C 2N X 10m = 20 joules of work Conclusion: the same amount of work is done in each scenario. Least force = C; A Force = 10N Least distance = A B Force = 4N C Force = 2N 5m 10m 2m 2m 2m 2m
Bridget and Ryan were racing home on their bicycles. Ryan decided to take a shortcut on Park Place while Bridget took Whitman Street. Ryan used 6 newtons of force, while Bridget only used 4 newtons. What can you conclude about their race? Component Ryan Bridget Conclusion Force Distance Work Park Place Whitman 4m 12m
Bridget and Ryan were racing home on their bicycles. Ryan decided to take a shortcut on Park Place while Bridget took Whitman Street. Ryan used 6 newtons of force, while Bridget only used 4 newtons. What can you conclude about their race? Component Ryan Bridget Conclusion Force Distance Work 6 newtons 4 newtons Ryan used more force 4 meters 12 meters Bridget traveled farther 24 joules 48 joules Bridget did more work Ryan Park Place 4m Bridget Whitman 12m
3N 7N Arrow size shows magnitude (strength) Are the forces Balanced or Unbalanced? Movement? Net Force (total force)?
3N 7N Arrow size shows magnitude (strength) Are the forces Balanced or Unbalanced? Unbalanced Movement? Left Net Force (total force)? 4N
Today s Task 1. Physics Practice 2. Plant Force Brochure/Foldable 3. Plant Force Practice ***All due tomorrow***