Question

Two blocks of masses 2 kg and 4 kg are hanging with the help of massless string passing over an ideal pulley
The tension in the string connected
inside an elevator. The elevator is moving upward with an acceleration
between the blocks will be (Take g = 10 m/s2).
(1) 40 N
(2) 60 N
(3) 80 N
(4) 20 N​

Answer 1

4(g +g/2)-t=4a...(1)

t-2(g+g/2)=2a...(2)

Therefore,

t-3g=2a=>t=3g+2a. Solving eqn 1from eqn (2),

4(g+g/2)-(3g+2a)=4a=>3g=6a=>a=g/2

Hence,

t=3g+2(g/2)t=40N

so the right answer is 40N

mark as brainlist

Answer 2

Answer: First option is correct.

Explanation:

Since we have given that

Mass of first block = 2 kg

Mass of second block = 4 kg

g = 10m/s²

and acceleration = $\dfrac{g}{2}=\dfrac{10}{2}=5\ m/s^2$

We need to find the tension in the string connected inside an elevator.

Tension = mg+ma

The elevator is moving upward with an acceleration between the blocks will be $g+\dfrac{g}{2}=\dfrac{3g}{2}$

So, tension would be

$\dfrac{3\times gm_1\times m_2}{m_1+m_2}\\\\\\=\dfrac{3\times 10\times 4\times 2}{6}\\\\=\dfrac{240}{6}\\\\=40\ N$

Hence, First option is correct.