Question

II) One 3.2-kg paint bucket is hanging by a massless cord from another 3.2-kg paint bucket, also hanging by a massless cord, as shown in Fig. 4-49. ( ) If the buckets are at rest, what is the tension in each cord? ( ) If the two buckets are pulled upward with an acceleration of 1.25 m/s by the upper cord, calculate the tension in each cord

Answer 1

Answer:

Here , mass of bucket ,m = 3.2 Kg

Now , let the tension in upper rope is T1

the tension in the middle rope is T2

a)

For lower bucket, balancing forces in vertical direction

T2 - mg = 0

T2 = mg

T2 = 3.2 *9.8

T2 = 31.36 N

tension in the middle rope is 31.36 N

For the upper bucket , balancing forces in vertical direction

T1 - T2 - mg = 0

T1 = T2 + 3.2 *9.8

T1 = 62.72 N

the tension in the upper rope is 62.72 N

B)

for a = 1.25 m/s^2

Using second law of motion ,for both the buckets

Fnet = ma

T1 - 2mg = 2m*a

T1 = 2*3.2*(9.8 +1.25)

T1 = 70.72 N

the tension in the upper rope is 70.7 N

Now , the lower bucket

Using second law of motion,

T2 - mg = ma

T2 = 3.2 * (9.8 + 1.25)

T2 = 35.36 N

the tension in the lower rope is 35.36 N