Unit 15 LESSON 1 WHAT ARE FORCES? - WordPress.com · 11/15/2018 · Unit 15 LESSON 1 WHAT ARE FORCES? Unit 15 Lesson 1 What Are Forces? Copyright © Houghton Mifflin Harcourt Publishing

Unit 15LESSON 1 WHAT ARE FORCES?

Unit 15 Lesson 1 What Are Forces?

Copyright © Houghton Mifflin Harcourt Publishing Company


Pushing and Pulling


• A force is a push or pull.

• Forces can cause an object at rest to move, speed up, slow down, change direction, or stop.

• Forces can change the shape of an object.

../../G6 1st semester lessons/Unit 15-lesson 1/15.1 images/Force.PNG

15.1 videos/Force Work and Energy Relationship - Videos for Kids by www.makemegenius_com.mp4


Pushing and Pulling


• For example, when rowers pull back on oars, the oars push against the water. The water pushes back against the oars, causing the boat to move.

• The larger the force, the greater the change it can cause to the motion of an object. Smaller forces cause smaller changes.

R1 More Force = More change in motion (acceleration)


Pushing and Pulling



Pushing and Pulling


• Spring scales are used to measure

force in units called Newton (N).

• Weight is the measurement of the

pull of gravity on an object. while,

Mass is a measurement of the amount

of matter something contains

• The unit of measuring weight is

Newton (N) while the unit of

measuring mass is g/Kg


Pushing and Pulling


Two Common Forces


Gravity

• Gravity is a force of attraction toward the center of Earth. It acts even when objects are not touching.


../../G6 1st semester lessons/Unit 15-lesson 1/15.1 images/gravity.PNG

15.1 videos/Gravity, Force, and Work (clip).mp4

Two Common Forces


Gravity


Two Common Forces


Gravity

• The size of the force increases as the mass of the objects increases.

• R2 more Mass = more Gravity


Two Common Forces


Gravity


Two Common Forces


Gravity

• The size of the force decreases as the distance between the objects increases.

• R3 More Distance = less gravity


Friction

• Friction is a force that opposes motion and acts between two objects that are touching.

• Friction can also exist between air and a moving object. This is called air resistance.

• Friction can also change the energy of motion into thermal energy.

• R4 more friction = less motion



../../G6 1st semester lessons/Unit 15-lesson 1/15.1 images/friction.PNG

15.1 videos/What is Friction_ _ Mocomi Kids.mp4

Friction



R5 smooth surface = less friction

rough surface = more friction

R6 more mass = more friction

Friction




Balanced or Unbalanced?


• Balanced forces are forces on an object that are equal in size and opposite in direction.

• Unbalanced forces are forces that cause a change in motion.

• A force must overcome the force of friction before an object will move.

../../G6 1st semester lessons/Unit 15-lesson 1/15.1 images/balanced forces.PNG

../../G6 1st semester lessons/Unit 15-lesson 1/15.1 images/unbalanced forces.PNG

15.1 videos/Balanced and unbalanced forces.wmv











Pull (or Push) Harder!


15.1 videos/Speed, Velocity, and Acceleration Physics of Motion Explained.mp4




• A large force will cause a large change in the motion of an object. A small force will cause little change.

• The large force makes the object change its velocity, or accelerate, quickly.

• Changes in velocity include changes in speed and changes in direction.

• R1 More Force = More change in motion (acceleration)

15.1 videos/Newton's 3 (three) Laws of Motion - trimmed.mp4


I’m Not Moving!


• The larger the force applied to an object, the greater the acceleration.




• What should the boy do differently to make the bell ring?


I’m Not Moving!


• When the same force is applied, objects with greater mass accelerate more slowly than objects with less mass.

•R7 more mass = less acceleration


I’m Not Moving!


• The less an object’s mass is, the less force is needed to change its motion.

•R8 less mass = less force


I’m Not Moving!



I’m Not Moving!


• Why does it take the full truck longer to stop than the empty truck?


Let’s Go to Mars!


• An understanding of forces helped to safely send a spacecraft to Mars.

15.1 videos/How do Rockets Work_ Basic Principle _ Mocomi Kids.mp4


Let’s Go to Mars!


• Balanced forces allowed a spacecraft to move in one direction at a constant velocity through space.

• Once the spacecraft reached Mars, it accelerated toward the surface because of gravity.

15.1 videos/How to Get to Mars. Very Cool! HD.mp4


Let’s Go to Mars!



Let’s Go to Mars!






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Unit 15 LESSON 1 WHAT ARE FORCES? - WordPress.com · 11/15/2018 · Unit 15 LESSON 1 WHAT ARE FORCES? Unit 15 Lesson 1 What Are Forces? Copyright © Houghton Mifflin Harcourt Publishing