QOD#48 What does each line represent? A – B – C – D – Time Distance Acceleration (speeding up) A B C D deceleration (slowing down) Stopped – no motion Constant Speed
QOD#48What does each line represent?A – B – C – D – Time
Dis
tanc
e
Acceleration (speeding up)
A
B
C
D
deceleration (slowing down)
Stopped – no motion
Constant Speed
ForcesForce – a push or pull on an object.
Unit – Newtons (N)
Types of ForcesA. ________________ - a force that is
applied when two objects touch.1. Push
ex:2. Pull
ex:
Contact forces
3. ___________________ - the resistance between two surfaces that are in contact with each other (sliding against each other).
ex:4. ___________________ - the force exerted on an object by the air as its moving. (drag
force)ex:
5. ___________________ - the upward force exerted by a fluid, which opposes the weight of an object.
ex:
Friction
Air resistance
Buoyancy
B. ____________________ - a force that one object applies to another object without touching.
1. ____________________ex:
2. ____________________ (includes static electricity)ex:
3. ____________________ex:
Non-Contact Force
Magnetic Force
Electric Force
Gravitational Force
Gravity
Buoyancy
Lift
Gravity
Thrust (push)
Drag (air resistance)
Forces WS
QOD #49Falling Feather & Golf Ball
1. What happens when we drop a golf ball and a feather down a stairwell?
2. Why does this happen?
Gravity________________ – the gravitational force exerted on an object.
Every object (that has mass) exerts a __________________________ of attraction on any other object.
Weight
gravitational force
Mass
The greater the mass of two objects, the ________________ the gravitational force is between them.
greater
Does the earth & the person or the moon & the person have a
greater gravitational force between them? Why?
DistanceThe force of gravity increases as two objects become ____________ (as the distance between the objects ______________).
The force of gravity decreases as two objects ____________________ (as the distance between the objects ______________).
closerdecreases
move farther apartincreases
Which person will feel a greater force of gravity with the
earth?
1. Between which two objects is there the greatest gravitational force (based on their mass)?a.
b.
c.
2. Between which two objects is there the greatest gravitational force (based on their distance)?a.
b.
c.
Measuring ForceForce is measured in Newtons (N)
1 Newton = lifting a stick of butter
20 Newtons = lifting a 2-L bottle of soda
Measuring Force ActivityObject Weight in Newtons (N)
QOD#50
•What is the speed of a giraffe if it travels 400 meters in 40 seconds?
Egg Drop Project
Balanced/Unbalanced ForcesForces are described in terms of ___________ and ____________ (strength).
directionmagnitude
Ex1: Pushing the box to the right
100 N
Ex2: Downward gravitational force
3 N
The ______________ is the combination of all the forces acting on an object.
net force
Ex3: Gravitational force of 15 NLift force of 15 N
Net force: __________ 0 N
Ex4:
650 N 400 N
Net force: __________ 1,050 N
Ex5:
125 N 375 N
Net force: __________ 250 N
____________________ – forces acting on any object that combine and form a net force of zero.
-When balanced forces are acting on an object, the object _________________.
Balanced forces
stays still
Ex6: 300 N 300 N
Net force: __________0 N
__________________ - forces acting on an object that combine to a net force that is not zero.
-Objects go into ___________because of unbalanced forces.
Unbalanced forces
motion
Ex7: 400 N 500 N
Net force: __________100 N
Balanced/Unbalanced WS
My Example:1. Draw a picture of a scenario with the forces and direction of
the forces labeled. 2. Another classmate is going to figure out the net force of your
made up scenario.3. Have the answer in your head. Don’t write it down in your
notebook.4. Switch notebooks with someone else, and write down the net
force in their notebook.