Motion, Forces, and Energy

1. Motion, Forces, and Energy 4th Grade Science S4P3 Students will demonstrate the relationship between the application of a force and the resulting change in position and motion on an object.

2. Motion, Forces, and Energy • GPS: S4P3 Students will demonstrate the relationship between the application of a force and the resulting change in position and motion on an object.

3. Motion, Forces, and Energy • Main Idea: Objects move when they change their position. • A frame of reference must be established. • What frame of reference do we use in these?: • Clock • Sunset • Base runner in baseball

4. Motion • Motion is a change in position of an object. • Things can move quickly or slowly.

5. Speed • Speed is the distance an object moves in a certain amount of time. • Distance divided by time = D/T • Need to know the distance and the time to calculate speed. • Examples: 60miles/hour, 50 yards /second

6. Velocity • Velocity is a measure of two things: the speed an object is moving and the direction an object is moving • Velocity = speed + direction • Example: A plane is flying 500 mph/West

7. Acceleration • Objects in motion often change their speed. • They can speed up or slow down. • They can change their direction. • Any change in the speed or direction of a moving object is called acceleration.

8. How Do Forces Affect Motion? • Forces can be a push or a pull. • Forces can be big or small. • Forces make object start moving, stop moving, slow down, speed up, or change direction. • Forces are measured in units called newtons. • Forces game

9. Balanced vs. Unbalanced Forces • If forces are balanced there is no change in the motion of an object • If forces are unbalanced there is a change in the motion of an object

10. Gravity • Gravity is pulling you towards Earth’s surface. • Gravity pulls two objects with mass together – gravitation. • The force of gravity between objects depends on two things – mass and how close together the objects are • More mass = stronger gravitational pull • Closer together = stronger gravitational pull • What goes up – must come down.

11. Weight • Weight is a measure of force. • It is the amount of gravity acting on an object. • How does your weight change if you should visit the Moon, Jupiter, Mars, or Saturn? • When you are weightless, there is no gravity pulling at you. • Brain Pop on Gravity

12. Friction • Friction is a force that works against motion. • There can be a lot of friction or sometimes very little. • The amount of friction can determine the motion of an object. • What objects create a lot of friction? • What objects have little friction? • Friction game

13. Inertia • An object at rest will stay at rest unless there is a force that acts upon it. • An object in motion will stay in motion unless there is a force that acts upon it. • This is why we wear seatbelts! • Brain Pop – Newton’s Laws

14. What is work? • Workis done when a force is used to move an object a certain distance. • To do work, a force needs to push or pull on an object and the object needs to move in the direction of the force.

15. Energy • In science, energy is the ability to do work. • Energy is needed to apply a force to an object to make it move. • Energy is needed to make matter change. • Energy is what makes the motion and change happen.

16. Forms of Energy

17. Energy Can Change Form • Energy does not always stay in one form. • Energy can change form. • Energy can be passed from one object to another. • Potential energy is stored energy – a lump of coal, an unused battery, a piece of candy • Kinetic energy is energy a moving object has – a running person, a burning candle, a falling ball.

18. Motion, Forces, and Energy • Energy is all around us. • Forces are used to change motion. • Energy comes in many different forms and can be changed from one form to another. • Energy allows you and other object to do work. • Knowing about energy can help us use it wisely!