Question

A person of mass 60 kg is inside a lift of mass 940 kg and posses the button on control panel . The lift starts moving upwards with an acceleration 1 m/ s2. If g= 10 m/s2 the tension in the supporting cable is

Answer 1

T = m(g + a)
T = 1000 * (10 + 1)
T = 11000 N

Answer 2

Answer:

The tension is 11000 N

Solution:

The mass of a person is given as 60 kg who is "inside a lift" of mass 940 kg, starts moving upwards then the tension in the supported cable is the force due to gravity  as well as acceleration, which can be calculated as follows -  

Given, the mass of person = 60 kg

Mass of lift = 940 kg

Total mass = mass of lift + mass of person

Total mass = 940 + 60 = 1000 kg

Now, to have acceleration, the tension created in the supported cable must be equal to the force due to gravity as well as acceleration.

$\mathrm{T}=\mathrm{mg}+\mathrm{ma}$

$\mathrm{T}=\mathrm{m}(\mathrm{g}+\mathrm{a})$

$\mathrm{T}=1000(10+1)$

$\mathrm{T}=1000(11)$

$\mathrm{T}=11000 \ \mathrm{N}$