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Willjeezy
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Homework Statement
A simple pendulum is 5m long. What is the period of the oscillations for this pendulum in an elevator accelerating upwards at 5m/s2 and accelerating downards at 5m/s2
Homework Equations
ω = √(g/L)
T = 2∏ / ω
The Attempt at a Solution
I got the right answers (trial and error), although I don't understand the concept.
for accelerating upwards.
ω = √[(9.8+5) /5]
ω = √[(14.8) /5]
^----this above part is confusing to me. If gravity is pointing down, and we have upward acceleration, shouldn't the value of (g + a) be smaller? I don't understand the meaning of 14.8 m/s2
I think the way the equation is defined confuses me.
ω = √(g/L)
the algebra of the equation doesn't confuse me, I understand why g can not be negative because of the root. However, if gravity always points down, and we let gravity be positive 9.8m/s, shouldn't and upward acceleration be defined as pointing in the negative direction?
thus shouldn't it be : ω = √[(9.8m/s2 MINUS 5m/s2) /5] ??
can someone explain the sign conventions? I have confused myself.
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