kinematics Speed, velocity and acceleration Graphical analysis of motion Free-fall Kinematics

Distance & displacement Kinematics

Distance & displacement Distance is the total length travel irrespective of the direction of motion. It is a scalar quantity. Displacement is the distance moved in a particular direction. It is a vector quantity. Kinematics

Actual length covered by moving body irrespective the direction Shortest distance between initial and final position Kinematics

Distance taken with consideration of direction Aspect Distance Displacement Definition Total route by a motion Distance taken with consideration of direction Type of quantity Scalar quantity Vector quantity SI Unit metre / m Kinematics

Displacement example If you walk 2 km from home to school, and 2 km back to school to home, then you have travelled a total distance of 4 km. On the other hand, as your final position is the same as your initial position, your displacement is zero. A physics teacher walks 4 meters East, 2 meters South, 4 meters West, and finally 2 meters North. What is the total distance travelled? What is the boy’s displacement from P? Kinematics

Speed & velocity Kinematics

Speed & velocity The speed of an object is the distance moved by the object per unit time. It also is defined as the rate of change of distance. The common units for speed are metres per second (m s-1) and kilometres per hour ( km h-1). Kinematics

This average speed is also known as the instantaneous speed. Example 2 For most journeys, speed is not constant. Normally we take the journey as a whole and calculate the average speed. This average speed is also known as the instantaneous speed. Example 2 If a car is taken from the garage, driven for 100 km before returning to the garage after 2 hours, what is it average speed? Kinematics

Velocity is also measured in m s-1 and km h-1. Velocity is the distance travelled per unit time in a specified direction. It is also defined as the rate of change of displacement. Velocity is also measured in m s-1 and km h-1. It is a vector quantity as the direction of travel is important. Kinematics

Rate of change of distance Rate of change of displacement Aspect Speed Velocity Definition Rate of change of distance Rate of change of displacement Type of Quantity Scalar Vector Formula = Total distance Time = Total displacement time SI Unit metre per second / m s-1 Kinematics

the distance travelled by the cyclist, Example 3 A cyclist travels 6 km due east and then makes a turn to travel a further distance of 8 km due north. The whole journey takes 2 hours. Calculate the distance travelled by the cyclist, the average speed of the cyclist, the displacement of the cyclist, the average velocity of the cyclist. Kinematics

Example 4 A boy run 5 km due west and then return back to travel a further distance of 4 km before resting. The whole journey takes 1 hour. Calculate his total distance travelled, his average speed, his displacement from the starting point, his average velocity. Kinematics

Example 5 A car starts from point O and moves to U, 50 m to the north in 60 s. The car then moves to B, 120 m to the west in 40 s. Finally, it stops. Calculate the: total distance moved by the car displacement of the car speed of the car when it is moves to the north velocity of the car average speed of the car Kinematics

example A car travels along the route PQRST in 30 minutes. What is the average speed of the car? 10 km / hour 20 km / hour 30 km / hour 60 km / hour Kinematics

A man crosses a road 8.0 m wide at a speed of 2.0 m / s. How long does the man take to cross the road? 4.0 s 6.0 s 10 s 16 s Kinematics

A child is standing on the platform of a station, watching the trains. A train travelling at 30 m / s takes 3 s to pass the child. What is the length of the train? 10 m 30 m 90 m 270 m Kinematics

A car driver takes a total of two hours to make a journey of 75 km A car driver takes a total of two hours to make a journey of 75 km. She has a coffee break of half an hour and spends a quarter of an hour stationary in a traffic jam. At what average speed must she travel during the rest of the time if she wants to complete the journey in the two hours? 38 km/ h 50 km/ h 60 km/ h 75 km/ h Kinematics

What is the average speed of the car for the whole journey? A car takes 1 hour to travel 100 km along a main road and then ½ hour to travel 20 km along a side road. What is the average speed of the car for the whole journey? 60 km / h 70 km / h 80 km / h 100 km / h Kinematics

0625/01/O/N/08 Q3 A car travels at various speeds during a short journey. The table shows the distances travelled and the time taken during each of four stages P, Q, R and S. Kinematics

During which two stages is the car travelling at the same speed? P and Q P and S Q and R R and S Kinematics

0625/01/O/N/03 Q4 A train travels along a track from Aytown to Beetown. The map shows the route. Kinematics

How long does the journey take? The distance travelled by the train between the towns is 210 km. It moves at an average speed of 70 km/ h. How long does the journey take? Kinematics

0625/01/M/J/08 Q3 The circuit of a motor racing track is 3 km in length. In a race, a car goes 25 times round the circuit in 30 minutes. What is the average speed of the car? 75 km / hour 90 km / hour 150 km / hour 750 km / hour Kinematics

0625/01/M/J/03 Q4 A tunnel has a length of 50 km. A car takes 20 min to travel between the two ends of the tunnel. What is the average speed of the car? 2.5 km/ h 16.6 km/ h 150 km/ h 1000 km/ h Kinematics

Acceleration Kinematics

acceleration Acceleration is defined as the rate of change of velocity. The SI unit for acceleration is m s-2. Acceleration is a vector quantity. The direction of acceleration is the direction of change in velocity. Kinematics

There is acceleration only when velocity changes. If velocity is constant throughout, there is no acceleration. If the velocity is increasing, the object is said to be accelerating. If the velocity is decreasing, then the object is said to have negative acceleration or deceleration or retardation. A body is said to move with uniform acceleration if its rate of change of velocity with time is constant. Kinematics

example A car accelerates from rest to 50 ms-1 in 10 s. Calculate the acceleration of the car. A car is uniformly retarded and brought to rest from a speed of 108 ms-1 in 15 s. Find its acceleration. The driver of a car brakes when the car is travelling at 30 ms-1. The velocity of the car is reduced to 10 ms-1 after 5 s. What is its average acceleration? Kinematics

If a car can accelerate at 3 If a car can accelerate at 3.2 ms-2, how long will it take to speed up from 15 ms-1 to 22 ms-1? How fast does a motorcycle travel if it starts at rest and is going 22 ms-1 after 5 seconds? What is the acceleration of a car that speeds up from 12 ms-1 to 30 ms-1 in 15 seconds? A truck travelling at 25 ms-1 puts its brakes on for 4 s. This produces a retardation of 2 ms-2. What does the truck’s velocity drop to? Kinematics

How fast does a car travel if it is going 4 m/s and accelerates at 3 How fast does a car travel if it is going 4 m/s and accelerates at 3.5 m/s2 for 5 seconds? If a car is going at 12 m/s, how long will it take to reach a speed of 26 m/s if it accelerates at 2.2 m/s2? A car moving along a straight level road has an initial speed of 3 m/s and its acceleration is 2 m/s2. What is the speed of the car after 5 s? Kinematics

A car sets off from a traffic lights A car sets off from a traffic lights. It reaches a speed of 27 m/s in 18 s. What is its acceleration? A train, initially moving at 12 m/s, speeds up to 36 m/s in 120 s. What is its acceleration? Kinematics

Ticker tape diagrams Kinematics

A common way of analyzing the motion of objects in physics labs is to perform a ticker tape analysis. Kinematics

One tick is equal to 1/50 s or 0.02 s. A ticker tape timer consists of an electrical vibrator which vibrates 50 times per second.  The time interval between two adjacent dots on the ticker-tape is called one tick.  One tick is equal to 1/50 s or 0.02 s. Kinematics

example Find the number of ticks and the time interval between the first dot and the last dot on each of the ticker tapes below. The frequency of the ticker timer is equal to 50Hz. Kinematics

The trail of dots provides a history of the object's motion and is therefore a representation of the object's motion. The distance between dots on a ticker tape represents the object's position change during that time interval. A large distance between dots indicates that the object was moving fast during that time interval. A small distance between dots means the object was moving slow during that time interval. Kinematics

Pattern Explanations The distance between the dots is the same. It shows that the object is moving with constant speed. The distance between the dots is short. It shows that the speed of the object is low. The distance between the dots is far. It shows that the object is moving at a high speed Kinematics

The analysis of a ticker tape diagram will also reveal if the object is moving with a constant velocity or with a changing velocity (accelerating). Kinematics

Pattern Explanations The distance between the dots is increased. It shows that the speed of the object increases. The distance between the dots is decreased. It shows that the speed of the object decreases. Kinematics

Displacement-time graph Kinematics

s = 10 m Kinematics

At rest Gradient = 0 Hence, velocity = 0 Kinematics

s = 0 m 10 m 20 m 30 m 40 m 50 m Kinematics

uniform velocity Gradient is constant, Hence, velocity is uniform Kinematics

s = 0 m 2 m 8 m 18 m 32 m 50 m Kinematics

acceleration Gradient is increasing Hence velocity is increasing. Kinematics

deceleration Gradient is decreasing Hence velocity is decreasing. Kinematics

Gradient of displacement-time graph 𝑔𝑟𝑎𝑑𝑖𝑒𝑛𝑡= 𝑐ℎ𝑎𝑛𝑔𝑒 𝑖𝑛 𝑦−𝑎𝑥𝑖𝑠 𝑐ℎ𝑎𝑛𝑔𝑒 𝑖𝑛 𝑥−𝑎𝑥𝑖𝑠 ∆𝑦 y-axis 𝑔𝑟𝑎𝑑𝑖𝑒𝑛𝑡= 𝑑𝑖𝑠𝑝𝑙𝑎𝑐𝑒𝑚𝑒𝑛𝑡 𝑡𝑖𝑚𝑒 𝑔𝑟𝑎𝑑𝑖𝑒𝑛𝑡=𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦 𝑜𝑓 𝑜𝑏𝑗𝑒𝑐𝑡 ∆𝑥 x-axis Kinematics

Velocity-time graph Kinematics

s = 0 m Kinematics

At rest Kinematics

s = 0 m 10 m 20 m 30 m 40 m 50 m Kinematics

uniform velocity Kinematics

s = 0 m 2 m 8 m 18 m 32 m 50 m Kinematics

Uniform acceleration Kinematics

Uniform deceleration Kinematics

Non-uniform acceleration Increasing acceleration Kinematics

Non- uniform deceleration Decreasing acceleration Kinematics

Gradient of velocity-time graph 𝑔𝑟𝑎𝑑𝑖𝑒𝑛𝑡= 𝑐ℎ𝑎𝑛𝑔𝑒 𝑖𝑛 𝑦−𝑎𝑥𝑖𝑠 𝑐ℎ𝑎𝑛𝑔𝑒 𝑖𝑛 𝑥−𝑎𝑥𝑖𝑠 ∆𝑦 y-axis 𝑔𝑟𝑎𝑑𝑖𝑒𝑛𝑡= 𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦 𝑡𝑖𝑚𝑒 𝑔𝑟𝑎𝑑𝑖𝑒𝑛𝑡=𝑎𝑐𝑐𝑒𝑙𝑒𝑟𝑎𝑡𝑖𝑜𝑛 𝑜𝑓 𝑜𝑏𝑗𝑒𝑐𝑡 ∆𝑥 x-axis Kinematics

Area under the graph of velocity-time graph 𝐴𝑟𝑒𝑎 𝑜𝑓 𝑅𝑒𝑐𝑡𝑎𝑛𝑔𝑙𝑒=𝑊𝑖𝑑𝑡ℎ×𝐿𝑒𝑛𝑔𝑡ℎ width 𝐴𝑟𝑒𝑎 𝑜𝑓 𝑅𝑒𝑐𝑡𝑎𝑛𝑔𝑙𝑒=𝑉𝑒𝑙𝑜𝑐𝑖𝑡𝑦×𝑇𝑖𝑚𝑒 𝑉𝑒𝑙𝑜𝑐𝑖𝑡𝑦×𝑇𝑖𝑚𝑒=𝐷𝑖𝑠𝑝𝑙𝑎𝑐𝑒𝑚𝑒𝑛𝑡 𝐴𝑟𝑒𝑎 𝑢𝑛𝑑𝑒𝑟 𝑡ℎ𝑒 𝑔𝑟𝑎𝑝ℎ=𝐷𝑖𝑠𝑝𝑙𝑎𝑐𝑒𝑚𝑒𝑛𝑡 length Kinematics

Interpreting graph From the displacement-time graph Its gradient gives the velocity of the moving object. From velocity-time graph Its gradient gives the acceleration of the moving object. The area under the graph gives the distance travelled by the object Kinematics

Example 1 Figure below shows the velocity a cyclist as she cycled through a town. Kinematics

What was the cyclist’s velocity after 60 s? How long did she have to wait at the traffic light? Which was larger, her deceleration as she stopped at the traffic lights, or her acceleration when she started again? Explain your answer. What is her total distance travelled for 120 s of the journey? Kinematics

Example 2 Figure below represents graphically the velocity of a bus moving along a straight road over a period of time. Kinematics

What does the portion of the graph between 0 and A indicate? What can you say about the motion of the bus between B and C? What is the acceleration of the bus between C and D? What is the total distance traveled by the bus in 100 s? What is the average velocity of the bus? Kinematics

Example 3 The graph below shows how the velocity of a certain body varies with time, t. Kinematics

Calculate the acceleration during the first 10 s shown on the graph. During the period t = 30 s to t = 45 s the body decelerates uniformly to rest. Complete the graph and obtain the velocity of the body when t = 38 s. Obtain the distance travelled by the body during the period t = 30 s and t = 45 s. Kinematics

Example 4 A cyclist started from rest achieved a speed of 10 m s-1 in 5 s. He then cycled at this speed constantly for the next 15 s. Finally he decelerate to complete his 30 s journey. Sketch a velocity-time graph for the whole journey? Calculate his deceleration in the last 10 seconds of the journey. Calculate the distance that he travelled during the journey. Kinematics

velocity (m/s) 10 5 20 30 time (s) Kinematics

𝑎𝑐𝑐𝑒𝑙𝑒𝑟𝑎𝑡𝑖𝑜𝑛=𝑔𝑟𝑎𝑑𝑖𝑒𝑛𝑡 𝑜𝑓 𝑔𝑟𝑎𝑝ℎ= 𝑦 2 − 𝑦 1 𝑥 2 − 𝑥 1 𝑎𝑐𝑐𝑒𝑙𝑒𝑟𝑎𝑡𝑖𝑜𝑛= 10−0 20−30 𝑎𝑐𝑐𝑒𝑙𝑒𝑟𝑎𝑡𝑖𝑜𝑛= 10 −10 =−1 𝑚/ 𝑠 2 Kinematics

𝑡𝑜𝑡𝑎𝑙 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑡𝑟𝑎𝑣𝑒𝑙𝑙𝑒𝑑=𝑎𝑟𝑒𝑎 𝑢𝑛𝑑𝑒𝑟 𝑔𝑟𝑎𝑝ℎ 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑡𝑟𝑎𝑣𝑒𝑙𝑙𝑒𝑑= 1 2 (15+30)(10) 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑡𝑟𝑎𝑣𝑒𝑙𝑙𝑒𝑑= 1 2 (45)(10)=225 𝑚 Kinematics

Example 5 A locomotive pulling a train out from one station travels along a straight horizontal track towards another station. The following describe the velocity of the train varies with time over the whole journey. It started from rest and gain a speed of 40 ms-1 in 2 s. It then travel with this speed constantly for 10 s. Finally it decelerates and reach the other station within 2 s. Kinematics

Example 5 Using the information given Sketch a velocity-time graph for this journey. Find the acceleration of the train in the first 2 s. the total distance travel between the two stations. the average velocity of the train. Kinematics

velocity (m/s) 40 2 12 14 time (s) Kinematics

𝑎𝑐𝑐𝑒𝑙𝑒𝑟𝑎𝑡𝑖𝑜𝑛=𝑔𝑟𝑎𝑑𝑖𝑒𝑛𝑡 𝑜𝑓 𝑔𝑟𝑎𝑝ℎ= 𝑦 2 − 𝑦 1 𝑥 2 − 𝑥 1 𝑎𝑐𝑐𝑒𝑙𝑒𝑟𝑎𝑡𝑖𝑜𝑛= 40−0 2−0 𝑎𝑐𝑐𝑒𝑙𝑒𝑟𝑎𝑡𝑖𝑜𝑛= 40 2 =20 𝑚/ 𝑠 2 Kinematics

𝑡𝑜𝑡𝑎𝑙 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑡𝑟𝑎𝑣𝑒𝑙𝑙𝑒𝑑=𝑎𝑟𝑒𝑎 𝑢𝑛𝑑𝑒𝑟 𝑔𝑟𝑎𝑝ℎ 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑡𝑟𝑎𝑣𝑒𝑙𝑙𝑒𝑑= 1 2 (14+10)(40) 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑡𝑟𝑎𝑣𝑒𝑙𝑙𝑒𝑑= 1 2 (24)(40)=480 𝑚 Kinematics

𝑎𝑣𝑒𝑟𝑎𝑔𝑒 𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦= 𝑡𝑜𝑡𝑎𝑙 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑡𝑟𝑎𝑣𝑒𝑙𝑙𝑑 𝑡𝑜𝑡𝑎𝑙 𝑡𝑖𝑚𝑒 𝑡𝑎𝑘𝑒𝑛 𝑎𝑣𝑒𝑟𝑎𝑔𝑒 𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦= 480 14 𝑎𝑣𝑒𝑟𝑎𝑔𝑒 𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦=34.3 𝑚/𝑠 Kinematics

What must change when a body is accelerating? the force acting on the body the mass of the body the speed of the body the velocity of the body Kinematics

Which of the following defines acceleration? Kinematics

Which quantity X is calculated using this equation? acceleration average velocity distance travelled speed Kinematics

A car is brought to rest in 5 s from a speed of 10 m / s. What is the average deceleration of the car? 0.5 m / s2 2 m / s2 15 m / s2 50 m / s2 Kinematics

A tennis player hits a ball over the net. Kinematics

In which position is the ball accelerating? P and Q only P and R only Q and R only P, Q and R Kinematics

The diagram shows a strip of paper tape that has been pulled under a vibrating arm by an object moving at constant speed. The arm was vibrating regularly, making 50 dots per second. Kinematics

What was the speed of the object? 2.0 cm / s 5.0 cm / s 100 cm / s 200 cm / s Kinematics

Which speed / time graph applies to an object at rest? Kinematics

B The speed-time graph shown is for a bus travelling between stops. Where on the graph is the acceleration of the bus the greatest? B Kinematics

A skier is travelling downhill A skier is travelling downhill. The acceleration on hard snow is 4 m / s2 and on soft snow is 2 m / s2. Which graph shows the motion of the skier when moving from hard snow to soft snow? Kinematics

C Kinematics

The graph shows the speed of a car as it accelerates from rest. During part of this time the acceleration is uniform. Kinematics

What is the size of this uniform acceleration? 5 m/s2 6 m/s2 10 m/s2 20 m/s2 Kinematics

The diagram shows a speed-time graph for a body moving with constant acceleration. Kinematics

What is represented by the shaded area under the graph? acceleration distance speed time Kinematics

The graph illustrates the motion of an object. Kinematics

Which feature of the graph represents the distance travelled by the object whilst moving at a constant speed? area S area S + area T area T the gradient at point X Kinematics

A cyclist is riding along a road when an animal runs in front of him A cyclist is riding along a road when an animal runs in front of him. The graph shows the cyclist’s motion. He sees the animal at P, starts to brake at Q and stops at R. Kinematics

What is used to find the distance travelled after he applies the brakes? the area under line PQ the area under line QR the gradient of line PQ the gradient of line QR Kinematics

The diagram shows the speed-time graph for an object moving at constant speed. Kinematics

What is the distance travelled by the object in the first 3 s? 1.5 m 2.0 m 3.0 m 6.0 m Kinematics

A car accelerates from traffic lights A car accelerates from traffic lights. The graph shows how the car’s speed changes with time. Kinematics

How far does the car travel before it reaches a steady speed? 10 m 20 m 100 m 200 m Kinematics

The graph represents the movement of a body accelerating from rest. Kinematics

After 5 seconds how far has the body moved? Kinematics

The graph shows the movement of a car over a period of 50 s. Kinematics

What was the distance travelled by the car during the time when it was moving at a steady speed? Kinematics

The graph shows the movement of a car over a period of 50 s. Kinematics

What was the distance travelled by the car while its speed was increasing? 10 m 20 m 100 m 200 m Kinematics

The graph represents part of the journey of a car. Kinematics

What distance does the car travel during this part of the journey? 150 m 300 m 600 m 1200 m Kinematics

question 1 Kinematics

Question 2 Kinematics

Question 3 Kinematics

Question 4 Kinematics

Question 5 Kinematics

Question 6 Kinematics

Free fall Kinematics

Falling freely A free falling object is an object that is falling under the sole influence of gravity. Any object that is being acted upon only by the force of gravity is said to be in a state of free fall. Kinematics

There are three important motion characteristics that are true of free- falling objects: Free-falling objects do not encounter air resistance. All free-falling objects (on Earth) accelerate downwards at a rate of 9.8 m/s2 (often approximated as 10 m/s2) Not affected by mass and shape of the object. Kinematics

Velocity Time Kinematics

SKYDIVING At the start of his jump the air resistance is zero so he accelerate downwards. Kinematics

As his speed increases his air resistance will also increase SKYDIVING As his speed increases his air resistance will also increase Kinematics

SKYDIVING Eventually the air resistance will be big enough to balance the skydiver’s weight. Kinematics

How the forces change with time. KEY Gravity (constant value & always present…weight) Air resistance (friction) Net force (acceleration OR changing velocity)

The size of the air resistance on an object depends on the area of the object and its speed; the larger the area, the larger the air resistance. the faster the speed, the larger the air resistance. Kinematics

skydiving When he opens his parachute the air resistance suddenly increases, causing him to start slow down. Kinematics

skydiving Because he is slowing down his air resistance will decrease until it balances his weight. The skydiver has now reached a new, lower terminal velocity. Kinematics

Velocity-time graph for the sky diver Parachute opens – diver slows down Speed increases… Terminal velocity reached… Velocity Diver hits the ground New, lower terminal velocity reached Time

A small steel ball is dropped from a low balcony. Ignoring air resistance, which statement describes its motion? It falls with constant acceleration. It falls with constant speed. It falls with decreasing acceleration. It falls with decreasing speed. Kinematics

C A student drops a table-tennis ball in air. What happens to the velocity and to the acceleration of the ball during the first few seconds after release? C Kinematics

Two stones of different weight fall at the same time from a table Two stones of different weight fall at the same time from a table. Air resistance may be ignored. What will happen and why? A Kinematics

The three balls shown are dropped from a bench. Which balls have the same acceleration? aluminium and lead only aluminium and wood only lead and wood only aluminium, lead and wood Kinematics

Which graph shows the motion of a heavy, steel ball falling from a height of 2 m? Kinematics

A stone falls freely from the top of a cliff into the sea A stone falls freely from the top of a cliff into the sea. Air resistance may be ignored. Which graph shows how the acceleration of the stone varies with time as it falls? D Kinematics

An object is falling under gravity with terminal velocity. What is happening to its speed? It is decreasing to a lower value. It is decreasing to zero. It is increasing. It is staying constant. Kinematics

At which position does she have terminal velocity? The diagrams show a parachutist in four positions after she jumps from a high balloon. At which position does she have terminal velocity? C Kinematics

Which graph represents the motion of a body falling vertically that reaches a terminal velocity? Kinematics

The speed-time graph for a falling skydiver is shown below The speed-time graph for a falling skydiver is shown below. The skydiver alters his fall first by spreading his arms and legs and then by using a parachute. Which part of the graph shows the diver falling with terminal velocity? D Kinematics

Question 1 (a) (i) weight or gravity (ii) air resistance or drag or friction (b) (i) 9.8 m/s2 or 10 m/s2 (ii) air resistance increases to oppose gravity or air resistance increases as speed increases (iii) air resistance = weight or downward force balances upward force or no resultant force Kinematics

Question 2 (a) (i) 9.8 m/s2 or 10 m/s2 (b) (i) air resistance = weight or downward force balances upward force or no resultant force (ii) weight larger than air resistance or downward force greater than upward force (c) coin and paper accelerate at 10 m/s2 hit bottom at the same time not fall at same time Kinematics

Question 3 (a) decelerating uniformly and comes to rest at 4 s (b) (i) 40 m/s (ii) 4 s (c) acceleration= change in speed time acceleration= 40−0 4 acceleration = 10 m/s2 (c) distance=area under the graph distance= 1 2 ×40×4 distance = 80 m Kinematics

KINEMATICS LEARNING OUTCOMES Kinematics

SPEED, VELOCITY & ACCELERATION State what is meant by speed and velocity. Calculate average speed using distance travelled/time taken. State what is meant by uniform acceleration and calculate the value of an acceleration using change in velocity/time taken. Discuss non-uniform acceleration. Kinematics

GRAPHICAL ANALYSIS OF MOTION Plot and interpret speed-time and distance- time graphs. Recognise from the shape of a speed-time graph when a body is at rest, moving with uniform speed, moving with uniform acceleration, moving with non-uniform acceleration. Calculate the area under a speed-time graph to determine the distance travelled for motion with uniform speed or uniform acceleration. Kinematics

FREE-FALL State that the acceleration of free-fall for a body near to the Earth is constant and is approximately 10 m/s2. Describe qualitatively the motion of bodies with constant weight falling with and without air resistance (including reference to terminal velocity). Kinematics