Question

find out the acceleration of block B in the following system..

Answer 1

Answer: The acceleration of the block B is $a =7.35 m/s^{2}$.

Explanation:

Given that,

Mass of small block B = m

Mass of big block = 3 m

According to figure

$(3m)a= 3mg-3T$.....(I)

$T = ma$.....(II)

Now, put the value of T in equation (I)

$3ma= 3m\times9.8-ma$

$4ma = 3m\times 9.8$

$a = \dfrac{9.8\times 3}{4}$

$a =7.35 m/s^{2}$

Hence, the acceleration of the block B is $a =7.35 m/s^{2}$.

Answer 2

"Answer:  

To determine : The acceleration of the block B shown in figure.

Given: Mass of block B = m

Mass of the other block = 3m

$g=9.8m/s^2$

Calculation:

From the figure we can observe that there are three forces on the pulley over the mass 3m which can be equated as follows

$3m\times a=3mg-3T$

Where T is the tension of the string holding the mass 3m

3T=ma

3ma=3mg-ma

$4ma=3m\times 9.8$

$a=(9.8\times 3)/4=7.35 m/s^2$"