Question

An elevator weighing $6000kg$ is pulled upward by a cable with an acceleration of $5m/s^2$. Taking $g$ to be $10m/s^2$. Then the tension in the cable is-

• A. $6000N$
• B. $9000N$
• C. $60000N$
• D. $90000N$

Answer 1

The correct option is D $90000N$

If Tension is $T$ then total upward force will be $T-weight=T-6000\times g$

We subtracted the weight because weight is $downward$ and we are calculating net upward force.

Now according to Newton's Second Law $\text{Net Force = mass multiplied by acceleration in that direction}$

As acceleration is $5m{s}^2$

So $T-6000g=6000\times 5=30000$ so $T=30000+6000\times 10=90000N$

Tension is $90000N$ Option D is correct.