How the temperature of water increases with the time of heating


         A student carries out an experiment to investigate how the temperature of water increases with the time of heating. Diagram 1.1 shows the set up of the apparatus for the investigation. Before the heater is switched on the initial temperature, θ0 of the water is measured. Diagram 1.2 shows meniscus of the mercury column in the thermometer.

          Seorang pelajar menjalankan satu eksperimen untuk menyiasat bagaimana suhu   air bertambah dengan masa pemanasan. Rajah 1.1 menunjukkan susunan radas bagi penyiasatan itu. Sebelum pemanas dihidupkan, suhu awal, θ0 bagi air itu diukur. Rajah 1.2 menunjukkan meniskus bagi turus merkuri dalam termometer.


 



A stopwatch and the heater is switched on simultaneously. At time, t = 20 s, the temperature, θ,  of the water is read on the thermometer. Diagram 2.3 shows the meniscus of the mercury column in the thermometer.

         Sebuah jam randik dan pemanas dihidupkan serentak. Pada masa, t = 20 s, suhu, θ, bagi air itu dibaca pada termometer. Rajah 1.3 menunjukkan meniskus bagi turus merkuri dalam termometer itu.



         The procedure is repeated for heating time, t  = 40 s, 60 s, 80 s, 100 s and 120 s. The corresponding positions of the meniscus of the mercury column in the thermometer are shown in Diagrams 1.3, 1.4, 1.5, 1.6 and 1.7.
        
         Procedure itu diulang bagi masa pemanasan, t  = 40 s, 60 s, 80 s, and 100 s. Kedudukan-kedudukan meniskus bagi turus merkuri dalam termometer adalah seperti ditunjukkan dalam Rajah 1.4, 1.5, 1.6 and 1.7.





 
(a)     For the experiment described above, identify:
                  Bagi experiment yang diterangkan di atas, kenal pasti
                  (i)     the manipulated variable / pembolehubah dimanipulasikan

                           …………………………………………………………………………………
 [1 mark]
                  (ii)    the responding variable / pembolehubah bergerak balas

                           …………………………………………………………………………………
[1 mark]
                  (iii)   a constant variable / pembolehubah dimalarkan

                           …………………………………………………………………………………
 [1 mark]

        
         (b)    Explain how parallax error can be reduced when the reading of the thermometer is taken.
                  Cadangkan bagaimana ralat paralaks boleh dikurangkan apabila mengambil bacaan thermometer.
                                                                    …..….……………………………………………………………………………….
[1 mark]

         (c)(i) Based on Diagram 1.2, determine the initial temperature, θ0, of the water.
                  Berdasarkan Rajah 1.2, tentukan suhu awal, θ0, bagi air itu.

                           Initial temperature  /  suhu awal , θ0 = …………….
                                                                                                                                 [1 mark]

                  (ii)    Based on Diagrams 1.3, 1.4, 1.5, 1.6 and 1.7, determine the temperature, θ,  for the corresponding values of heating time, t.
Berdasarkan Rajah 1.3, 1.4, 1.5, 1.6 dan 1.7,tentukan suhu θ, untuk setiap nilai pemanasan dengan masa, t.


Δθ is the increase in temperature,  Δθ is calculated using the formula,
                                Δθ ialah kenaikan suhu, Δθ dikira menggunakan formula.
                            

 
Tabulate your results for t, θ and Δθ in the space below.
 Jadualkan keputusan bagi  t, θ and Δθ dalam ruang yang disediakan.





                                                                                                           







                                   
[5 marks]

         (d)    On the graph paper on page 6, plot a graph of Δθ against t.
                  Pada kertas graf di halaman 6, lukis graf Δθ melawan t.
                                                                                                                                  [5 marks]

         (e)     Based on your graph, state the relationship between Δθ and t.
                  Berdasarkan graf anda, nyatakan hubungan antara Δθ dan t.

                  …..….……………………………………………………………………………….
 [1 mark]



Graph Δθ against  t.


           






















































j