Question

A solution to this question.
Two objects with masses 3kg and 5kg are connected by a light string that passes over a light frictionless pulley to form an Atwood machine. Determine the tension in the string
B.the acceleration of each object
C. The distance each object will move in the first law of motion if the they start from rest

Answer 1

A. 36.8 N

B. 2.45 ms^(-2)

C. 1.22 m

Explanation:

According to Newton’s Law

∑Fy = ma(y)

For m1 = 3kg the above equation will be:

T – W1 = (3)(a)

T = 3a + m1*g = 3a + (3)(9.8) = 3a + 29.4 …….. (ii)

For m2= 5kg the above equation will be:

T – W2 = (5)(a)

T = 5a + m2*g = 3a + (5)(9.8) = 5a + 49    ………. (i)

Comparing (i) and (ii) and solving for a we get,

a = 2.45 ms^(-2)

putting this value in (ii) we get,

T = 36.8 N

Now,  

S = Vi*t + ½ at^2

Here, Vi = 0. By putting values we get,

S = 1.22 m