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Determine the speed of the 50-kg cylinder after it has descended a distance of 2 m, starting from rest. Gear A has a mass of 10 kg and a radius of gyration of 125 mm about its center of mass. Gear B and drum C have a combined mass of 30 kg and a radius of gyration about their center of mass of 150 mm

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This question is incomplete, the missing image is uploaded along this answer below.

Answer:

the speed of the 50-kg cylinder after it has descended is 3.67 m/s

Step-by-step explanation:

Given the data in the question and the image below;

relation between velocity of cylinder and velocity of the drum is;

V
_D = ω
_c × r
_c ----- let this be equ 1

where V
_D is velocity of cylinder, ω
_c is the angular velocity of drum C and r
_c is the radius of drum C

Now, Angular velocity of gear B is;

ω
_B = ω
_C

ω
_B = V
_D / r
_c -------- let this equ 2

so;

V
_D / 0.1 m = 10V
_D

Next, we determine the angular velocity of gear A;

from the diagram;

ω
_A( 0.15 m ) = ω
_B( 0.2 m )

from equation 2; ω
_B = V
_D / r
_c

so

ω
_A( 0.15 m ) = (V
_D / r
_c ) 0.2 m

substitutive in value of radius r
_c (0.1 m)

ω
_A( 0.15 m ) = (V
_D / 0.1 m ) 0.2 m

ω
_A( 0.15 ) = 0.2V
_D / 0.1

ω
_A = 2V
_D / 0.15

ω
_A = 13.333V
_D ----- let this be equation 3

To get the speed of the cylinder, we use energy conversation;

assuming that the final position is;

T₁ + ∑
U_{1-2 = T₂

0 + m
_Dgh =
(1)/(2)m
_D
_D +
(1)/(2)I_Aω²
_A +
(1)/(2)I_Bω²
_B

so

m
_Dgh =
(1)/(2)m
_D
_D +
(1)/(2)(m
_Ak
_A²)(13.333V
_D)² +
(1)/(2)(m
_Bk
_B²)(10V
_D

we given that; m
_D = 50 kg, h = 2 m, m
_A = 10 kg, k
_A 125 mm = 0.125 m, m
_B = 30 kg, k
_B = 150 mm = 0.15 m.

we know that; g = 9.81 m/s²

so we substitute

50 × 9.81 × 2 = (
(1)/(2) × 50 × V
_D²) +
(1)/(2)( 10 × (0.125)² )(13.333V
_D)² +
(1)/(2)( 30 × (0.15)²)(10V
_D

981 = 25V
_D² + 13.888V
_D² + 33.75V
_D²

981 = 72.638V
_D²

V
_D² = 981 / 72.638

V
_D² = 13.5053

V
_D = √13.5053

V
_D = 3.674955 ≈ 3.67 m/s

Therefore, the speed of the 50-kg cylinder after it has descended is 3.67 m/s

Determine the speed of the 50-kg cylinder after it has descended a distance of 2 m-example-1
User Harish Ambady
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