A) \[\frac{{{w}_{1}}+{{w}_{2}}}{2}\]
B) \[\frac{{{w}_{1}}-{{w}_{2}}}{2}\]
C) \[2\,{{w}_{1}}\]
D) \[2\,{{w}_{2}}\]
Correct Answer: A
Solution :
When lift moves down with constant acceleration a, then \[mg-{{w}_{2}}=2\,mg\] ?(ii) From Eq. (i) and (ii), we get \[{{w}_{1}}+{{w}_{2}}=2\,mg\] ?(iii) When lift moves up with constant speed, its acceleration is zero. So, \[w-mg=0\] or \[w=mg\] ?(iv) From Eq. (iii) and (iv) \[{{w}_{1}}+{{w}_{2}}=2\,w\] or \[w=\frac{{{w}_{1}}+{{w}_{2}}}{2}\]You need to login to perform this action.
You will be redirected in
3 sec