Question

Emily has three rods which are all the same size and are all composed of a pure substance. She wants to find out if all three rods are made of the same pure substance. To do this, she adds a piece of wax with a little bead on top to the end of each rod. She then heats up the opposite end of one rod using Bunsen burner. Emily waits for the rod to heat up completely so that the wax at the other end melts and the bead drops. She measures how long it takes for the bead to drop. She then repeats this process with the other two rods. The diagram below shows Emily's experimental setup. The results of her experiment are also shown below.

Based on this experiment and the results, what can be concluded?
A.
Rods A, B, and C are all made of different substances.
B.
Rod B is made of the same substance as rod C.
C.
Rod A is made of the same substance as rod B.
D.
Rods A, B, and C are all made of the same substance.

Answer 1

Answer: A

Step-by-step explanation:

Rod A took 45 seconds.

Rod B took 30 seconds which is 15 seconds less than Rod A

Rod C took 60 seconds which is 15 seconds more than Rod A, and 30 seconds more than Rod B.

If all of them were made of the same substance, they all would have the same time, since they all have different times, then they all are made of different substances.