An amusement park ride consists of a rotating circular platform 8.00 m in diameter from which 11.0 kg seats are suspended at the end of 2.50 m massless chains. When the system rotates, the chains make an angle θ=26.0o
with the vertical. Assume the average mass of a child is 40.0 kg.
(a) Find the speed of each seat.
(b) Find the tension in the chain.
(c) Did the speed depend on the mass?
(d) Did the tension depend on the mass?

Respuesta :

Answer:

a) 4.57 m/s^2

b) 556.1 N

c) No

d) Yes

Explanation:

from the question we are given the following

mass of each seat (M) = 11 kg

diameter of platform = 8 m

length of chain = 2.5 m

angle = 26 degrees

mass of each child (m) = 40 kg

acceleration due to gravity (g) = 9.8 m/s^2

we can get the tension in the vertical direction from the formula

T x cosθ = mg

T = mg / cos θ

also we can get the tension in the horizontal direction from the form[tex]\sqrt{x} \sqrt{(g x r x sin) / cos}[/tex]ula

T x sin θ = mv^2 / r   ( from the formula for centrifugal force )

T = ( mv^2) / rsin θ

equating the 2 formulas for tension we have  

mg / cos θ =  (mv^2) / rsin θ

g / cos θ =  (v^2) / rsin θ

sin θ / cos θ  = v^2) / gr

v = [tex]\sqrt{(g x r x sin θ ) / cos θ }[/tex]    ....equation  B

now lets calculate for r so we can substitute all values into the equation above

from the diagram below, the total extension of the seats from the center of the platform is =d/2 + (L x sinθ)

= 8/2 + (2.5 x sin 26) =4.38 m

now substituting all values into equation B we have

v = [tex]\sqrt{(9.8 x 4.38 x sin 26 ) / cos 26 }[/tex]

v = 4.57 m/s^2

b) tension in the chain is gotten by using the formula for tension

T cos θ = (M +m) x g

T =   ((M +m) x g) / cos θ

T =   ((40 +11) x 9.8) / cos 26

T = 556.1 N

c) Since the formula used to calculate the speed  ( v = [tex]\sqrt{(9.8 x 4.38 x sin 26 ) / cos 26 }[/tex] ), consists of the mass,  the speed does not depend on the mass.

d) Since the formula used to calculate the tension ( T =   ((M +m) x g) / cos θ ) consist of the mass,  the tension does depend on the mass.