The system shown to the right is a standard atwood machine. if the mass of b is 6.25 kg and the mass of a is 1.38 kg, how fast is block b accelerating?

Explanation:

Let's write the equations of motion for the two blocks:

where

T is the tension in cable

mA = 1.38 kg is the mass of block A

mB = 6.25 kg is the mass of block B

g = 9.8 m/s^2 is the gravitational acceleration

a = ? is the acceleration of the system

Solving the first equation for T we find

And substituting into the second one:

The acceleration 'a' of Block B is 6.26 .

Step-by-Step Explanation:

The mass of Block B is more than Block A so under the influence of gravitational acceleration 'g' = 9.8 The system will move such that Block B moves downward and Block A moves upward with an acceleration 'a'.

The net force 'F' that produces this acceleration 'a' is the difference in the weights of the two blocks.

F = ma

F = (mB) g - (mA) g     where mA = mass of block A , mB = mass of block B

⇒ ma = (mB) g - (mA) g   where m is the total mass of the system

(mA + mB)a = (mB) g - (mA) g

Hence; acceleration 'a' is given as:

if the person is shown to have +90n, then ans is -10n.

if the person is shown to have -90n, then ans is +10n.