Science
A group of sixth grade students is investigating the effect of the length of string on the number of swings (to and fro) a bob of pendulum can produce in one minute. The mass and the size of the bob are constant. The students obtained the following results:
Length of String (cm) Number of Swings in 1 minute
30 20
35 16
40 12
45 8

1. Which of the following problems do the students like to answer?
A. Does the mass of the bob affect the number of swings a pendulum can make in 1 minute?
B. Does the length of string affect the number of swings a pendulum can make in 1 minute?
C. Does the number of swings affect the length of string of a bob?
D. Does the mass of the bob affect the length of string?

2. Which of the following could be the BEST hypothesis that would lead the students to investigate?
A. The mass of the bob affects the number of swings a pendulum can make in 1 minute.
B. The length of string affects the number of swings a pendulum can make in 1 minute.
C. The number of swings affects the length of string of a bob.
D. The mass of the bob affects the length of the string.

3. Based on the gathered data, which of the following would be the conclusion?
A. The mass of the bob affects the number of swings a pendulum can make in 1 minute.
B. The length of string affects the number of swings a pendulum can make in 1 minute.
C. The number of swings affects the length of string of a bob.
D. The mass of the bob affects the length of string.