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3 years ago

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What is the maximum speed when the conditions are mass =450 kg, initial height= 30 m, and the roller coaster is initially at res

t?
A. 30 m/s
B. 24.2 m/s
C. 93.9 m/s
D. 132, 300 m/s

1 answer:

Zarrin [17]3 years ago

3 0

Answer:

B. 24.2 m/s

Explanation:

Given;

mass of the roller coaster, m = 450 kg

height of the roller coaster, h = 30 m

The maximum potential energy of the roller coaster due to its height is given by;

$P.E_{max} = mgh\\\\PE_{max} = 450 *9.8*30\\\\PE_{max} = 132,300 \ J$

$P.E_{max} = K.E_{max} \ (law \ of \ conservation\ of \ energy)$

$K.E_{max} = \frac{1}{2}mv_{max}^2\\\\ v_{max}^2 = \frac{2K.E_{max}}{m}\\\\ v_{max}^2 = \frac{2*132300}{450}\\\\ v_{max}^2 =588\\\\v_{max} = \sqrt{588}\\\\ v_{max} = 24.2 \ m/s$

Therefore, the maximum speed of the roller coaster is 24.2 m/s.

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