What is the Maximum Safe Upward Acceleration of a Block Lifted by a Crane?

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The maximum safe upward acceleration of a concrete block lifted by a crane with a maximum load of 1.2 * 10^4 N and a mass of 1000 kg is calculated to be 2.2 m/s². The initial calculation mistakenly considered only the maximum load without accounting for gravitational force acting on the block. The correct approach involves determining the net force by subtracting the weight of the block from the crane's maximum load. This results in a net force of 2190 N, leading to the final acceleration calculation. Thus, the maximum safe upward acceleration is confirmed to be 2.2 m/s².
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Homework Statement


A crane has a maximum safe working load of 1.2 * 10^4 N and is used to lift a concrete block of mass 1000kg. What is the maximum safe upward acceleration of the block while being lifted?

Homework Equations


F=ma

The Attempt at a Solution


F=mα
1.2*10^4=1000*α
α= 12m/s2The answer is 2.2 m/s2
 
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raamishstuden said:

Homework Statement


A crane has a maximum safe working load of 1.2 * 10^4 N and is used to lift a concrete block of mass 1000kg. What is the maximum safe upward acceleration of the block while being lifted?


Homework Equations


F=ma


The Attempt at a Solution


F=mα
1.2*10^4=1000*α
α= 12m/s2


The answer is 2.2 m/s2

You seem to have forgotten that while the crane is pulling up, gravity is pulling down, so the net force is much less than 1.2*10^4 N
Acceleration is the result of the net force.
 
Oh! I got it. Here is the solution. Is it right?

F-f=ma
(1.2*10^4)-(9.81*1000)=1000*a
2190=1000a
a=2.19
=2.2 ms-2
 
raamishstuden said:
Oh! I got it. Here is the solution. Is it right?

F-f=ma
(1.2*10^4)-(9.81*1000)=1000*a
2190=1000a
a=2.19
=2.2 ms-2

That's more like it.
 
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