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What is the approximate length of a pendulum that takes 2.4 pi seconds to swing back and forth?

1.72 ft

3.05 ft

38.40 ft

46.08 ft

User Andromida
by
4.8k points

2 Answers

3 votes

Answer:

46.08 ft

Explanation:

User Blade
by
5.0k points
4 votes

Answer:

The approximate length of the pendulum is 46.08 ft

Explanation:

The time (t) of pendulum oscillation is given as;


t = 2 \pi\sqrt{(L)/(g) }

where;

L is the length of the pendulum

g is acceleration due to gravity = 9.8 m/s² = 32.15 ft/s²

t is the time given as 2.4 π seconds

From the equation above, make L the subject of the formula;


t = 2 \pi\sqrt{(L)/(g) } \\\\(t)/(2\pi) = \sqrt{(L)/(g) }\\\\((t)/(2\pi) )^2 =(L)/(g) \\\\L = g*((t)/(2\pi) )^2\\\\L = 32.15*((2.4 \pi)/(2\pi) )^2\\\\L = 32.15 *1.44\\\\L = 46.296 \ ft

Therefore, the approximate length of the pendulum is 46.29 ft

The closest option is 46.08 ft

User Sabastian
by
4.5k points