# Homework Help: Pendulum in water

1. Jun 26, 2008

### liz6

1. The problem statement, all variables and given/known data

first question: If a simple pendulum with a period of 1 second is set in motion on the moon,determine the new period of this pendulum.

second question: If a pendulum is made to swing in water,compare the time taken for this pendulum to come to a complete stop with the time taken by a pendulum swinging in air. Explain the difference.

2. Relevant equations

T=2(3.142)x(1/g)^1/2

3. The attempt at a solution

first question: the pendulum will swing forever on the moon because it is in a vacuum rite? but what does it mean by determine the new period?
the graph of period Ts against length for this question will be a straight line parallel to the x axis..?

second question: if a pendulum is made to swing in water, the resistance is higher compare to air rite? so the time taken for a pendulum to come to a complete stop is shorter compare to a pendulum swinging in the air...so the answer should be resistance?
but what is the graph of pendulum in water (period against length) would be like? is it a curve? have a lower gradient compare to the graph of pendulum in air?

i just want to make sure i did right for my coursework. thx for your help.
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

2. Jun 26, 2008

### nicksauce

The period depends on g. g is different on the moon. Hence the period will be different.