Physical quantities Physical quantities A physical quantity is

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Physical quantities

Physical quantities

Physical quantities • A physical quantity is quantity which can be measured. • For

Physical quantities • A physical quantity is quantity which can be measured. • For example: length, mass, time, temperature, electric current, light intensity, volume and many others. • A physical quantity is a property of a material that can be quantified by measurement. • A physical quantity is always measured of natural non-living objects.

 • Physical quantities have numerical magnitude and unit. • For example: if the

• Physical quantities have numerical magnitude and unit. • For example: if the length of a student is 104 cm. Then 104 is its numerical magnitude and cm is the unit of measurement. • Physical quantities describe physical properties of an object by measurements. It consists of: • Magnitude: The amount. • Units: what is the scale used to measure.

SYSTEM INTERNATIONAL (SI) UNITS

SYSTEM INTERNATIONAL (SI) UNITS

 • The international system of units is the standard modern form of the

• The international system of units is the standard modern form of the metric system. The name of this system can be shortened or abbreviated to SI from the French name system international d unities. • The international system of units is a system of measurements base on 7 base units: the meter (length), kilogram (mass), second (time), ampere (electric current), kelvin (temperature), mole (quantity), and candela (brightness).

 • This creates SI units which can be used to describe other quantities,

• This creates SI units which can be used to describe other quantities, such as volume, energy, pressure, and velocity • The system is used almost globally. Only Liberia and the united state do not used SI as their official system of measurement. • In these countries though SI is commonly used science and medicine.

Instruments for measurement

Instruments for measurement

Definition of Instruments • “A scientific instrument is broadly speaking, a device or tool

Definition of Instruments • “A scientific instrument is broadly speaking, a device or tool used for scientific purposes, including the study of both natural phenomenon and theoretical research”.

Measurement • Measurement is an important part of science, construction, art, design and a

Measurement • Measurement is an important part of science, construction, art, design and a wide array of other professional fields. There are hundred of measuring tools. Each measuring instrument serves a specific purpose for the person who is using it. There a few measuring instruments that are more commonly seen than others”.

Meter rule • Definition: A meter rule is a device which is used to

Meter rule • Definition: A meter rule is a device which is used to measure length of different objects. A meter rule of length 1 m is equal to 100 centimeters. On meter rule each centimeter is divided further into 10 divisions which are called millimeters (mm). So, a meter rule can measure up to 1 mm as smallest reading. • Accuracy: While meter rule is the most simple tool to measure objects with medium length. The accuracy rate of meter rule is 0. 1 cm which makes it a best option when measuring medium lengths.

Measuring cylinder • Definition: A graduated cylinder (or measuring cylinder) is a piece of

Measuring cylinder • Definition: A graduated cylinder (or measuring cylinder) is a piece of laboratory glass ware used to measure the volume of liquids. It is used to accurately measure the volume of chemical for use in reaction. • Accuracy: For accuracy the volume on graduated cylinder is significant digits: 100 ml cylinders have 1 ml grading division while 10 ml cylinder have 0. 1 ml grading divisions. Two classes of accuracy exists for graduated cylinders.

Flasks • Definition: A flask is a bottle which you use for carrying drinks

Flasks • Definition: A flask is a bottle which you use for carrying drinks around with you. A flask is bottle or other container which is used in science laboratories and industry for holding liquids. • Accuracy: According to indigo instruments, the accuracy of a beaker is about 10 percent. A graduated cylinder is accurate to 1 percent of it full scale.

Pipettes • Definition: A small piece of apparatus which typically consists of a narrow

Pipettes • Definition: A small piece of apparatus which typically consists of a narrow tube into which fluid is drawn by suction and retained by closing the upper end. • Accuracy: A pipette is accurate to the degree that the volume delivered is equal to the specified volume. Pipetting accuracy is critical to successful experiments.

Accuracy and Precision in measurement

Accuracy and Precision in measurement

> Accuracy is how close a measurement is to the correct value for that

> Accuracy is how close a measurement is to the correct value for that Measurement. >The precision of a measurement system is refers to how close the agreement is between repeated measurements (which are repeated under the same conditions). > Measurements can be both accurate and precise, accurate but not precise, precise but not accurate, or neither.

Example • Suppose your height is 183 cm. If we measure it with some

Example • Suppose your height is 183 cm. If we measure it with some instrument (measuring tape and a fancy laser beam!) it comes out to be 182. 9995 cm. Another measurement (with a meter rod and a 6 th grader) yields a result of 195 cm. We can see that the value obtained from the first measurement is closer to the actual value (true value) of your height. So the first measurement is more accurate in comparison to the second one.

 • Let’s suppose that our 6 th grader likes to measure heights. He

• Let’s suppose that our 6 th grader likes to measure heights. He takes three more measurements of your height and gets the following results: 197 cm, 195. 3 cm, and 196. 1 cm. Are these measurements accurate? Of course not, they are far from the true value of your height. But we see that all these measurements are close to each other i. e. 197 cm, 195. 3 cm, 196. 1 cm and 195 cm are close to each other. They are precise measurements.

How to apply method • High accuracy, low precision On this bullseye, the hits

How to apply method • High accuracy, low precision On this bullseye, the hits are all close to the center, but none are close to each other; this is an example of accuracy without precision.

 • Low accuracy, high precision On this bullseye, the hits are all close

• Low accuracy, high precision On this bullseye, the hits are all close to each other, but not near the center of the bullseye; this is an example of precision without accuracy.

Laboratory work

Laboratory work

 • The aim of laboratory work is to deepen and fix theoretical knowledge

• The aim of laboratory work is to deepen and fix theoretical knowledge and to develop the skills of independent experimentation. • Laboratory work is widely used in teaching the natural sciences and technical disci plines • The work includes preparing the equipment necessary for an experiment, planning the experiment and carrying out the experiment. • 60– 70 percent of the time is spent on laboratory work. This Photo by Unknown Author is licensed under CC BY-SA

Planning and organization • Scientists consider how their work should be organized. which could

Planning and organization • Scientists consider how their work should be organized. which could be based on themes, teams, projects or fields of expertise. • Work is divided, not only between different jobs of the laboratory such as the researchers, engineers and technicians. • Some forms of organization in laboratories include: Their size: Varies from a handful of researches to several hundred. • The division of labor: Occurs between designers, researchers, engineers and technicians. •

Three main factors • There are three main factors that contribute to the organizational

Three main factors • There are three main factors that contribute to the organizational form of a laboratory : • The educational background of the researchers and their socialization process. • The intellectual process involved in their work, including the type of investigation and equipment they use. • The laboratory's history.

General lab safety rules • Be sure to read all fire alarm and safety

General lab safety rules • Be sure to read all fire alarm and safety signs and follow the instructions in the event of an accident or emergency. • Ensure you are fully aware of your facility's/building's evacuation procedures. • Make sure you know where your lab's safety equipment—including first aid kit(s), fire extinguishers, eye wash stations, and safety showers—is located and how to properly use it. • Know emergency phone numbers to use to call for help in case of an emergency. • Never lift any glassware, solutions, or other types of apparatus above eye level.

Precautions and safety measures • Laboratory hazards might include poisons, infectious agents, flammable, explosive

Precautions and safety measures • Laboratory hazards might include poisons, infectious agents, flammable, explosive or radioactive. • Therefore, safety precautions are vitally important. • Rules exist to minimize the individual's risk, and safety equipment is used to protect the lab users from injury or to assist in responding to an emergency. • The Occupational Safety and Health Administration (OSHA) in the United States has tailored a standard for occupational exposure to hazardous chemicals in laboratories.

Appropriate teaching methods • ACTIVITY BASED METHOD • EXPERIMENT BASED METHOD

Appropriate teaching methods • ACTIVITY BASED METHOD • EXPERIMENT BASED METHOD

What is activity based method: • Activity method is a technique adopted by a

What is activity based method: • Activity method is a technique adopted by a teacher to emphasize his or her method of teaching through activity in which the students participate rigorously and bring about efficient learning experiences

Why it is important: • Activity-based learning or ABL describes a range of pedagogical

Why it is important: • Activity-based learning or ABL describes a range of pedagogical approaches to teaching. Its core premises include the requirement that learning should be based on doing some hands-on experiments and activities. The idea of activity-based learning is rooted in the common notion that children are active learners rather than passive recipients of the information. If the child is provided the opportunity to explore by their own and provided an optimum learning environment then the learning becomes joyful and long-lasting

What is experiment method: • The experimentation that is done through an investigative, reflective

What is experiment method: • The experimentation that is done through an investigative, reflective and communicative way, combined with playfulness, not only provides the teacher a different way of teaching, but stimulate students to study and construct their own knowledge.

Why it is important: • The experimentation is essential for science teaching because it

Why it is important: • The experimentation is essential for science teaching because it allows the practical activities to integrate teacher and students, to provide a joint planning (in which teacher and student construct the process of the activity) and the use of teaching techniques that can lead to a better understanding of the science.

Why these 2 method are appropriate: • We selected this method because it increases

Why these 2 method are appropriate: • We selected this method because it increases the learning capabilities of the students. • Research shows that students gain and retain maximum knowledge when the perform something themselves listening and seeing the concepts do not remain long time in the brain. • So that’s why we selected activity and experiment based teaching learning So that students can perform themselves and explore the concept behind measurement techniques and accuary.

GROUP MEMBERS • Mahroop Suhail • Rija Toqeer • Aneeqa Tahir • Sinham Fatima

GROUP MEMBERS • Mahroop Suhail • Rija Toqeer • Aneeqa Tahir • Sinham Fatima • Rimsha Asghar • An’na Shabir • Laiba Kashif