Question

An elevator is required to lift a body of mass 65 kg. Find the
acceleration of the elevator, which could cause a reaction of
800 N on the floor.

Answer 1

Known:
m=65 kg
N=800 N
Asked: acceleration (a) ?
Answer:
Find weight (w):
w=m x g
Consider the acceleration of gravity (g) is 9,8 m/s² or 10 m/s² .
So,
w=65 x 10
   =650 N

Next,use this formula:
ΣF=m.a
N-w=m.a
800-650=65.a
     150   =65.a
     150   =a
       65
      30    =a
      13
     2,3    =a

So ,acceleration is 2,3 m/s².

Answer 2

Step by Step explanation

Given: Mass is $65kg$ and $N=800N$

To find: Acceleration or $A$ of the elevator

For calculation of weight,

We know that $w= m$ × $g$

$g= 10m/s^{2}$

⇒ $w= 65$ × $10$

⇒ $w=650N$

For calculation of acceleration,

We know that ∑$F= m$ × $a$ or $N-w= m$ × $a$

⇒ $800-650= 65$ × $a$

⇒ $150= 65$ × $a$

⇒ $\frac{150}{65} = a$

⇒ $\frac{30}{13} = a$

⇒$2,3=a$

The acceleration is $2,3m/s^{2}$.