Nothing Special   »   [go: up one dir, main page]
Scribd Logo
Upload

Welcome to Scribd!

  • 181 views

    Paper 6 Notes

    Uploaded by

    aliyameen2006
    This document provides guidance on safety precautions and procedures for conducting physics experiments accurately. It describes how to properly set up and carry out experiments to measure specific heat capacity, cooling rate of water, insulation properties, refraction and reflection of light, resistance and temperature, speed of sound, and center of mass. Tips are included on minimizing errors, such as avoiding parallax, taking repeated measurements, and controlling variables. Sources of inaccuracy in experimental methods and measurements are also discussed.

    Copyright:

    © All Rights Reserved
    Download as PDF, TXT or read online from Scribd

    Paper 6 Notes

    Uploaded by

    aliyameen2006
    181 views8 pages
    This document provides guidance on safety precautions and procedures for conducting physics experiments accurately. It describes how to properly set up and carry out experiments to measure specific heat capacity, cooling rate of water, insulation properties, refraction and reflection of light, resistance and temperature, speed of sound, and center of mass. Tips are included on minimizing errors, such as avoiding parallax, taking repeated measurements, and controlling variables. Sources of inaccuracy in experimental methods and measurements are also discussed.

    Original Description:

    2023

    Copyright

    © © All Rights Reserved

    Available Formats

    PDF, TXT or read online from Scribd

    Did you find this document useful?

    Is this content inappropriate?

    This document provides guidance on safety precautions and procedures for conducting physics experiments accurately. It describes how to properly set up and carry out experiments to measure specific heat capacity, cooling rate of water, insulation properties, refraction and reflection of light, resistance and temperature, speed of sound, and center of mass. Tips are included on minimizing errors, such as avoiding parallax, taking repeated measurements, and controlling variables. Sources of inaccuracy in experimental methods and measurements are also discussed.

    Copyright:

    © All Rights Reserved
    Download as PDF, TXT or read online from Scribd
    Download as pdf or txt
    181 views8 pages

    Paper 6 Notes

    Uploaded by

    aliyameen2006
    This document provides guidance on safety precautions and procedures for conducting physics experiments accurately. It describes how to properly set up and carry out experiments to measure specific heat capacity, cooling rate of water, insulation properties, refraction and reflection of light, resistance and temperature, speed of sound, and center of mass. Tips are included on minimizing errors, such as avoiding parallax, taking repeated measurements, and controlling variables. Sources of inaccuracy in experimental methods and measurements are also discussed.

    Copyright:

    © All Rights Reserved
    Download as PDF, TXT or read online from Scribd
    Download as pdf or txt
    You are on page 1of 8

    physics

    0625
    Shuen's P6!!

    notes

    @shuennotes
    Safety precautions
    Applies to most:
    ● Avoid parallax error by placing eyes at measured level.
    ● Reduce human reaction time
    ● Check for zero error (mm screw gauge, voltmeter etc)
    ● Safety goggles, gloves and other safety components should be used while handling
    experiments
    ● Hot objects should not be touched with bare hands - gloves should be used

    Electricity
    ● Live wires should not be touched.
    ● Circuit connections should be checked and approved by the teacher and then only
    the circuit should be switched on
    ● While changing components of the circuit the power should be switched so that one
    should not experience electric shocks

    Pendulum
    ● Swing bob from a small angle to maintain uniform oscillation over period of time
    ● Avoid parallax error of meter rule + avoid zero error of stopwatch
    ● Take repeated readings in timing to avoid random error
    ● Shut windows and turn off fans to avoid external air interference

    Light
    ● Align object with optical centre of lens
    ● Avoid parallax error of metre rule
    ● Ensure object, lens, screen are placed in a straight line (collinear arrangement)
    ● Clean lens to ensure clear image
    ● Make sure sharp image is formed before taking reading
    ● Close curtains and off lights to avoid external light interference (get sharp image)

    Miscellaneous
    ● While handling a mercury thermometer one should take care of the mercury spills.
    ● Eye same level as bottom of meniscus
    ● Card must suspend freely (for plumbline & card exp)
    Experiments
    SPECIFIC HEAT CAP
    Apparatus: Solid block, Drill, Thermometer, Heater (of known power), Cotton wool
    Procedure:
    1. Drill two holes in the block
    2. Measure the mass of the block
    3. Place the heater in one of the blocks, the thermometer in the other
    4. Use cotton wool to properly insulate/lag the block
    5. Note the initial temperature of block and turn on heater for 𝑥seconds
    6. Calculate Heat Energy Supplied by heater using formula Q=Pt
    7. Note the final temperature of block & calculate: ​𝑆𝑝𝑒𝑐𝑖𝑓𝑖𝑐 ℎ𝑒𝑎𝑡 𝑐𝑎𝑝𝑎𝑐𝑖𝑡𝑦 = 𝑄/(𝑚×∆𝑡)

    COOLING RATE OF WATER


    Apparatus: Heater, Thermometer, Beaker, Stopwatch, Beaker containing Water.
    Procedure:
    1. Place heater into beaker and turn it on to raise the temperature of water to 60°C
    2. Stir the contents of the water and place thermometer into the beaker
    3. Note the starting temperature and turn on the stopwatch
    4. Take readings of the thermometer and stopwatch at regular intervals (e.g. 60 sec)
    5. Draw up a table and plot a graph to conclude your experiment

    PICKING A BETTER INSULATOR


    Apparatus: Two large cans, two small cans, cotton wool, polystyrene beads, boiling water,
    thermometers, stopwatch
    Procedure:
    1. Put the small cans into the large cans and insulate the small can with cotton wool
    and polystyrene beads
    2. Pour boiling water into the small cans and place the thermometers in them
    3. Start the stopwatch and take readings of temperature at regular intervals
    4. Record readings in a table for each insulator
    5. The small can that has the higher temperature over the fixed period is better
    insulated
    6. Hence, object that provides a less temperature loss over the period is the better
    insulator.
    REFRACTION OF LIGHT
    Apparatus: Ray Box, Rectangular piece of glass, Plain paper, Pencil
    Procedure:
    1. Place the Plain paper below the rectangular piece of glass
    2. Project a ray towards the glass
    3. Make two points to mark the incident ray, two to mark the refracted ray and two to
    mark the emergent ray
    4. Join all the lines, measure the angles and calculate refractive index
    5. Repeat with different angles

    REFLECTION OF LIGHT
    Apparatus: Pins, Mirror
    Procedure:
    1. Shine beam from raybox to mirror
    2. Use the pencil to carefully mark two dots in the center of the incident and reflected
    rays
    3. Join the dots and complete the ray
    4. Draw a normal and measure the angles
    5. Angle i = Angle r, proving laws of reflection.

    RESISTANCE AND TEMPERATURE


    Apparatus: Resistor, Battery, Connecting wires, Ammeter, Voltmeter, Oven
    Procedure:
    1. Make a circuit with the battery, connecting wires, ammeter and voltmeter, resistor
    2. Measure the resistance of the resistor using the formula R=V/I
    3. Heat the resistor in the oven. Place the resistor back into the circuit
    4. Measure the readings again and calculate R=V/I
    5. Draw up a conclusion about how the resistance increases as temperature increases.

    SPEED OF SOUND
    Apparatus: Two observers, Gun, Stopwatch
    Procedure:
    1. Two observers are set apart at a known distance
    2. One observer has the gun, the other has the stopwatch
    3. Observer A fires the gun, Observer B starts the stopwatch when he sees the puff of
    smoke
    4. Observer B stops the stopwatch when he hears the sound and the time is noted
    5. 𝑆𝑝𝑒𝑒𝑑 = 𝐷𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑇𝑖𝑚𝑒 applied
    6. The observers swap positions and repeat the experiment
    7. The values are averaged and the speed of sound is obtained
    CENTRE OF MASS
    To find centre of mass of a plane lamina:
    1. Make a hole in the lamina
    2. Hang it so it can swing freely
    3. Hang a plumb line in the hole and mark the line it passes through
    4. Repeat the procedure again to get another line
    5. Their intersection point is the center of mass
    Stability of simple objects:
    ● The position of the center of mass affects an object’s stability. If the center of mass of
    an object is low, it is less likely to tip if tilted, increase stability
    ● To increase stability: Increase surface area // make the object shorter
    Improving accuracy
    To produce more accurate or reliable results:
    ● Repeat experiment, to calculate average reading
    ● Avoiding parallax error, look perpendicular to the ruler
    ● If accuracy in measurement was asked, check for zero error

    To draw an image created from lens:


    ● Inverted from the original object
    ● Sides are multiplied by the magnification

    Centre of mass experiment (with the lamina):


    ● view the string directly in front of the card.

    Minimizing heating effect of a current:


    ● Lower current
    ● Increase voltage
    ● Add a lamp
    ● increase resistance of a resistor

    To increase accuracy of ray diagrams:


    ● View bases of pins since pins may not be vertical
    ● Keep pins further apart and use more pins
    ● Avoid parallax
    ● Repeats and average

    Improvement made to experiments about heating/cooling effect and insulation


    ● Same initial temperature
    ● Same volume of water
    ● Same shape and type of beaker
    ● Same room temperature
    ● stirring the water in the beakers
    ● Record max. Temperature

    Heat loss could be reduced by:


    ● Insulation of beaker
    ● Covering beaker with a lid

    How to check if a rule is vertical:


    ● Use of set square or protractor
    ● Plumb line
    ● Spirit Level (an equipment but idt we used b4 but just in case la)
    Precautions taken in experiments about formation of images by a lens
    ● Use a darkened area
    ● Object and lens same height on bench
    ● Take more readings
    ● Avoiding parallax error in measurement, and look perpendicular to the ruler
    ● Object/lens/screen perpendicular to bench

    Variables in experiments about springs and stretching effect:


    ● Number of coils
    ● Length of spring
    ● Diameter\thickness of spring or wire
    ● Selection of loads

    improvements made to calculating circumference by string method


    ● Avoid parallax error
    ● Repeats and average
    ● Thinner string
    ● Parallel winding of springs

    Precautions for circuit readings of I and V so that accurate:


    For I specifically:
    ● Limit current so that temp. doesn't increase
    ● Use a tapping meter
    For I and V:
    ● Switch off between readings (prevent heating up)

    Fair test for pendulum experiments (at least one must be kept constant):
    ● Length of pendulum
    ● Shape of bob
    ● No. of swings
    ● Amplitude

    Precautions and procedures in electrical experiments


    ● Check for a zero error
    ● Tap the meter to avoid sticking (arrow doesn't move)
    ● Initially choose the highest range for the ammeter/voltmeter, then reduce the range
    for the ammeter so that the deflection is almost full scale
    ● Always check polarities before closing the switch (completing the circuit)
    ● Always check that connections are clean
    ● Switch off the current when not making a measurement
    ● When measuring resistance use low currents/voltages to avoid heating and changing
    the resistance you are measuring
    Inaccuracies
    Why angle i is NOT equal to angle r in ray experiment
    ● Thickness of pins
    ● Thickness of mirror
    ● Protractor is not precise

    Inaccuracy of ray box method​: thickness of rays

    Inaccuracy of pin method​: pins not straight, or too close, or thickness of lines drawn

    Measuring 10 oscillations rather than 1:​


    ● Reduce human errors
    ● Give more accurate value of time taken: gives an average of time

    You might also like