question_answer

The mass of a lift is 500 kg. When it ascends with an acceleration of \[\text{2}\,\text{m/}{{\text{s}}^{\text{2}}}\text{,}\] the tension in the cable will be: \[\text{(g}\,\text{=}\,\text{10}\,\text{m/}{{\text{s}}^{2}}\text{)}\]

A)  6000 N       

B)  5000 N

C)  4000 N       

D)  1000 N

Correct Answer: A

Solution :

 The resultant acceleration [a] is provided by resultant of tension [T] and weight (mg). Therefore, \[T-mg=ma\] \[\Rightarrow \] \[T=m(g+a)\] Given \[m=500\,kg,\,g=10\,m/{{s}^{2}},a=2m/{{s}^{2}}\] \[\therefore \] \[T=500(10+2)\] \[\Rightarrow \] \[T=6000\,N\]