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

Answer :

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

Explanation:

 Given the data in the question and the image below;

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

V[tex]_D[/tex] = ω[tex]_c[/tex] × r[tex]_c[/tex]  ----- let this be equ 1

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

Now, Angular velocity of gear B is;

ω[tex]_B[/tex] = ω[tex]_C[/tex]

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

so;

V[tex]_D[/tex] / 0.1 m = 10V[tex]_D[/tex]

Next, we determine the angular velocity of gear A;

from the diagram;

ω[tex]_A[/tex]( 0.15 m ) = ω[tex]_B[/tex]( 0.2 m )

from equation 2; ω[tex]_B[/tex] = V[tex]_D[/tex] / r[tex]_c[/tex]

so

ω[tex]_A[/tex]( 0.15 m ) = (V[tex]_D[/tex] / r[tex]_c[/tex] ) 0.2 m

substitutive in value of radius r[tex]_c[/tex] (0.1 m)

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

ω[tex]_A[/tex]( 0.15 ) = 0.2V[tex]_D[/tex] / 0.1

ω[tex]_A[/tex] =  2V[tex]_D[/tex]  / 0.15

ω[tex]_A[/tex] = 13.333V[tex]_D[/tex]   ----- let this be equation 3

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

assuming that the final position is;

T₁ + ∑[tex]U_{1-2[/tex] = T₂

0 + m[tex]_D[/tex]gh = [tex]\frac{1}{2}[/tex]m[tex]_D[/tex]V²[tex]_D[/tex] + [tex]\frac{1}{2}I_A[/tex]ω²[tex]_A[/tex] + [tex]\frac{1}{2}I_B[/tex]ω²[tex]_B[/tex]

so

m[tex]_D[/tex]gh = [tex]\frac{1}{2}[/tex]m[tex]_D[/tex]V²[tex]_D[/tex] + [tex]\frac{1}{2}[/tex](m[tex]_A[/tex]k[tex]_A[/tex]²)(13.333V[tex]_D[/tex])² + [tex]\frac{1}{2}[/tex](m[tex]_B[/tex]k[tex]_B[/tex]²)(10V[tex]_D[/tex])²

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

we know that; g = 9.81 m/s²

so we substitute

50 × 9.81 × 2 = ( [tex]\frac{1}{2}[/tex] × 50 × V[tex]_D[/tex]²) + [tex]\frac{1}{2}[/tex]( 10 × (0.125)² )(13.333V[tex]_D[/tex])² + [tex]\frac{1}{2}[/tex]( 30 × (0.15)²)(10V[tex]_D[/tex])²

981 = 25V[tex]_D[/tex]² + 13.888V[tex]_D[/tex]² + 33.75V[tex]_D[/tex]²

981 = 72.638V[tex]_D[/tex]²

V[tex]_D[/tex]² = 981 / 72.638

V[tex]_D[/tex]² = 13.5053

V[tex]_D[/tex] = √13.5053

V[tex]_D[/tex] = 3.674955 ≈ 3.67 m/s

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

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