Investigating the Factors that Affect the Period of One Swing of a Pendulum

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Investigating the Factors that Affect the Period of One Swing of a Pendulum

Aim: To investigate the factors which affect the period of one swing

(oscillation) of a simple pendulum. The factors I will use are length

of the string, and angle that the bob is released from.

Hypothesis:

1. Length of string

I think that the length of the string directly affects the period of

one oscillation. The mathematical formula used to describe the period

of the pendulum is:

T= 2 p√tex2html_wrap_inline105/g

T is the period (time for one swing - seconds)

tex2html_wrap_inline105 is the length of the pendulum (metres)

g is the acceleration dues to gravity. (N/KG)

tex2html_wrap_inline105 (Length) is in the formula, clearly indicating

that it is a factor which will directly affect the period of time.

To see whether the time period will increase or decrease when the

length is increased, I will substitute the formula for numbers to see

the result.

Length 0.3, g-force = 9.8N/KG

T= 2p √tex2html_wrap_inline105/g

T = 2p √0.3/9.8

T = 1.009s

Length 0.4, g-force = 9.8N/KG

T= 2p√tex2html_wrap_inline105/g

T = 2p √0.4/9.8

T = 1.269s

The calculations above show that when the length of the pendulum is

0.3m, the time for one oscillation is 1.009s. When the length is

increased, the time is increased. When length is 0.4m, time period is

1.269s.

This tells us that when the length is increased, the time period is

increased.

2. Angle of release

A simple pendulum is only a weight known as a "bob" hung from a

string. When the bob is lifted, the pendulum gains potential

gravitational energy, as it is acting against the force. Therefore,

the angle, which would raise the height, would give the bob more

gravitational energy (up to 90°). The more the angle, the more the

energy, the faster the swing, the less the period of time.

Prediction:

1. Length of string - I predict that the longer the length of string,

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