Static body. The object does not change its position as time passes.
Dynamic body :The object changes its position as time passes.
Types of motion Periodic motionTranslational motion It repeat its position in space at equal interval time. The motion of body from point to another. (in straight line – in curved line)
Scalar and Vector Vector QuantityScalar Quantity Has direction and magnitude such as (Velocity – displacement - acceleration ) The quantity which has magnitude only such as ( Time – volume – mass – distance - speed )
Check your understanding Categorize each quantity as being either a vector or a scalar. Category Quantity ( Scalar – Vector ) 5 m ( Scalar – Vector ) 30 m/sec, East ( Scalar – Vector ) 5 m., North ( Scalar – Vector ) 20 degrees Celsius ( Scalar – Vector ) 256 bytes ( Scalar – Vector ) 4000 Calories
Check your understanding Category Quantity Scalar ( Scalar – Vector ) 5 m Vector ( Scalar – Vector ) 30 m/sec, East Vector ( Scalar – Vector ) 5 m., North Scalar ( Scalar – Vector ) 20 degrees Celsius Scalar ( Scalar – Vector ) 256 bytes Scalar ( Scalar – Vector ) 4000 Calories
Distance (d) and displacement (X) DisplacementDistance - The distance traveled in a certain direction. - Or It is the change in the position The actual path the body moved in it. Vector Scalar Displacement is 5 meters. rightward Distance is 5 meters.
Distance (d) and displacement (X) when the car travels from (A) to (B) to (C) and then to (D). the distance "the path"= = 15Km. The displacement between (A) initial point to (D) end point is 9Km Mansora MetMazah Dekerness A D Demoh C B 10Km 3Km 2Km 9Km
Ex: A car travels from the A to B,C, and D in the direction shown.. Find the distance and displacement in each of the following. 1-When the car travels from A to B 2- When the car travels from A to C 3- When the car travels from A to D 4-When the car travels from A to B,C,D then to A 30Km 50Km A B C D
Ex: A car travels from the A to B,C, and D in the direction shown.. Find the distance and displacement in each of the following. 1-When the car travels from A to B 2- When the car travels from A to B to C 3- When the car travels from A to B to C to D 4-When the car travels from A to B,C,D then to A 30Km 50Km A B C D Answer: From A to B to C to D to A from A to B to C to Dfrom A to B to CFrom A to B Distance (km) Displacement (km)
Use the diagram to determine the resulting displacement and the distance traveled by the skier during these three minutes Worksheet 1
Speed and Velocity VelocitySpeed The change of displacement per unit of time. How fast in which direction. 50 m/s north is a velocity. The change of distance per unit time. How fast an object is moving. 50 m/s is a speed.
Types of velocity The non-uniform velocityThe uniform (constant) velocity Displacement changed by different amount at equal interval of time. Displacement changed by equal amounts at equal intervals of time. Instance velocity: It is the velocity of moving body at certain instance. The average velocity: Is the total displacement traveled per the total time
Ex: A car moves at constant speed of 20m/s how far is the car after an hour? RemarksFindGiven X distancev=20m/s t=1h×60m×60s = 3600s Distance X = v × t = 20 × 3600 = m
The physics teacher walks 4 meters East, 2 meters South, 4 meters West, and finally 2 meters North. The entire motion lasted for 24 seconds. Determine the average speed and the average velocity. Problem
Problem The physics teacher walked a distance of 12 meters in 24 seconds; thus, her average speed was 0.5 m/s. displacement is 0 meters, her average velocity is 0 m/s
is the change of velocity in one second An object is accelerating if it is changing its velocity.
Problem A car moves from rest with uniform acceleration 2 m/s 2. During 4 seconds.Calculate the final speed.
Problem V i = 0 m/s VfVf Acceleration = 2 m/s 2 Then V f = 2 × 4 = 8 m/s 2
Use the equation for acceleration to determine the acceleration for the following two motions
a = (0 m/s - 8 m/s) / (4 s) a = (-8 m/s) / (4 s) a = -2 m/s/s Use a = (vf - vi) / t and pick any two points. a = (8 m/s - 0 m/s) / (4 s) a = (8 m/s) / (4 s) a = 2 m/s/s
Observe the animation of the three cars below 1. Which car or cars (red, green, and/or blue) are undergoing an acceleration? Study each car individually in order to determine the answer. The green and blue cars are speeding up, thus covering an increasing distance in each second. Red car has constant speed.
Observe the animation of the three cars below 2-Which car (red, green, or blue) experiences the greatest acceleration? The blue car has a greater acceleration. It is changing it velocity at more rate.
Observe the animation of the three cars below 3-Consider the position-time graph at the right. Each one of the three lines on the position-time graph corresponds to the motion of one of the three cars. Match the appropriate line to the particular color of ca Red car = B constant slop Green = C more gradually Blue car = A
Describe the motion depicted by the following velocity-time graphs. In your descriptions, make reference to the direction of motion (+ or - direction), the velocity and acceleration and any changes in speed (speeding up or slowing down) during the various time intervals (e.g., intervals A, B, and C) he object moves in the + direction at a constant speed - zero acceleration (interval A). The object then continues in the + direction while slowing down with a negative acceleration (interval B). Finally, the object moves at a constant speed in the + direction, slower than before (interval C).
Ex: draw the graph relating d and t, then answer. the object moves with 1-an increasing velocity 2-a decreasing velocity 3-a uniform velocity the object moves with 1-an increasing acceleration 2-a decreasing acceleration 3- zero acceleration d(m) 321t(s) Worksheet 2
Relative Speed قوله تعالى : ( وَتَرَى الْجِبَالَ تَحْسَبُهَا جَامِدَةً وَهِيَ تَمُرُّ مَرَّ السَّحَابِ صُنْعَ اللَّهِ الَّذِي أَتْقَنَ كُلَّ شَيْءٍ إِنَّهُ خَبِيرٌ بِمَا تَفْعَلُونَ ) [ النمل : 88].
Jack Jill Speed is not absolute, it is dependant on the observer. That is why we say it is "relative" to the observer Observer Jill sees Jack at rest and Jack sees Jill the same way
Jack Jill Observer Mother is the observer
the Speed of A relative to B, the Speed of B relative to A is. The expression "the speed of A relative to B" is "the speed of A in the coordinate system where B is always at rest". Relative Speed All motion is relative to the observer or to some fixed object.
Relative Speed All motion is relative to the observer or to some fixed object. Two cars moving along the same straight road, The speeds are relative to the ground. Measurements of position and speed are made from some point on the ground, point O. Speed of car A relative to point O = vA(O) = 40ms-1 Speed of car B relative to point O = vB(O) = 30ms-1 What is the speed of car A relative to car B? A moves 10m away from B in the positive sense and B moves 10m away from A in the negative sense. Therefore, vA(B) =+10ms-1 and vB(A) = -10ms-1 vB(A) = vB(O) - vA(O) = 30 – 40 = -10ms-1
Suppose that we want to know the speed of car A relative to car B Worksheet 3
References %20traveled.htm l/ConstantAccel.html How to solve physics problem (Rebort Oman - Danial Oman ) Fundamentals of Physics Extended, 8th Edition [Jearl Walker], Cleveland State University, John Wi ley & Sohs, lnc. 2007, downloaded from ( ) Student book (science for prep3 – term1 – )
Mr. Hmady Eid (website)