A kettle of water is heated and the temperature of the water, j°C, after k minutes, is given by j = 5k + 30. Copy and complete the table. Graph the
relationship between k and j. Use 1 unit on the horizontal axis to represent
1 minute and 1 unit on the vertical axis to represent 5°C.
a)
Time (k
minutes)
0
2
4
6
b)
What is the temperature of the water after 5 minutes?
c)
What is the average rate of the heating?
d)
Assuming the temperature of the water rises at a constant rate, what is
the temperature of the water after 10 minutes?
e)
The kettle of water needs to be heated till the water boils. For how
many minutes does the kettle need to be heated? Express your answer
in terms of k, where k stands for the number of minutes. (Hint: Water
boils at 100°C.)