Motion, Forces & Machines PowerPoint Presentation

Did you ever wonder what powered the rocket or how fast it went? Both of those questions can be related to motion , forces and mechanics.

Speed The speed of an object is the distance the object travels per unit of time. Speed is a rate which tells you the amount of something that occurs or changes in one unit of time. Speed=distance over time Speed can be divided into two subtitles constant speed & average speed.

Constant & Average Speed constant speed is the speed that does not change. Average speed is the total by time. distance divided

Velocity Velocity is Speed in a given direction. If you know the velocity of an object you know its speed and velocity. Velocity is a vector quantity. its also “direction-aware”. The direction of the velocity vector is simply the same as the direction which an object is moving. If going downward the velocity is downward. If going upward the velocity is upward.

Acceleration The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object. Acceleration=force over mass

Weight & Mass Weight is a measure Mass is an object Of the force of gravity On you. Weight is a Useful measurement Of how much matter An object has. Mass is an object that will not change If the force of gravity on its changes. mass is a Useful physical property for Describing and measuring matter. The SI unit of mass is Kilograms.

Newton's 1st Law of Motion An object at rest tends to stay at rest and an object in motion tends to stay in motion with the same speed and in the same direction unless acted upon by an unbalanced force.   sometimes referred to as the "law of inertia." There are two parts one which predicts the behavior of stationary objects and the other which predicts the behavior of moving objects . The two parts are summarized in the following diagram.

Example of 1st Law of Motion Pendulum is a example for Newton's first law Once its in motion its always in motion. Once its at rest its always at rest.

Newton's 2nd Law of Motion The second law states that the acceleration of an object is dependent upon two variables - the net force acting upon the object and the mass of the object. It explains the relation of force, mass & acceleration. Force=mass x acceleration The net force on an object is equal to the product of its acceleration and its mass.

Newton’s 3rd Law of Motion A force is a push or a pull upon an object which results from its interaction with another object. Action force and reaction force

Work, Force , Efficiency, Mechanical Advantage , and Power Exerting forces on the object than causes the same object to move some direction To work you must move some distance

Force Is a push or pull It can be divided into two subtitles unbalanced and balanced Unbalanced force can cause an object to start moving, stop moving , or change balanced force is equal forces on an object will change the object motion

Example of unbalanced force

Mechanical advantage A machine is a devise witch makes it easier to do work It changes the amount of force you have to use, the distance you have to move, or the duration you have to go in

Efficiency The efficiency of a machine compares the out put work is to the input work It is expressed in percent The higher the percent is the better the efficiency Efficiency=output work over input work x 100%

Power Is the rate witch work is done for the amount of work done in a unit of time Power=work over time Power=force x distance over time Is a rate witch energy is transformed from one object to another or one form to another

Simple & Complex Machines Simple machines There are six basic kinds of machines: the inclined plane, the wedge, the screw, the lever, the wheel an axle & pulley. Complex machines are two or more simple machines working together Machines of all types make work easier by changing the size or direction of an applied force.

Difference between Powered Vehicles and Rockets rockets and powered vehicles are both examples of machines

Bibliography www.united streaming. COM Physical science textbook http://classroom.jc-schools.net/sci-units/force.htm#8