Question

The mass of a lift is `2000kg` . When the tensioon in the supporting cable is `28000N` , then its acceleration is.
A. `30ms^(-2)` downwards
B. `4ms^(-2)` upwards
C. `4ms^(-2)` downwards
D. `14ms^(-2)` upwards

Answer 1

Correct Answer - B
Apparent weightgtactual weight, then the lift is acceleration upward. Here, lift is acceleration upward at rate of a. Hence, equation of motion is written as
`R-mg=ma`
`28000-20000=2000a`
implies `a=(8000)/(2000)=4ms^(-2)` upwards.