Question

A crane uses a petrol engine to lift a heavy girder. What is the overall energy conversion in system when the girder is moving at a steady rate??
A) chemical into KE
B) Chemical into PE

Answer 1

I think

B is answer.....

Answer 2

$\bold{ CORRECT\:\: OPTION\: :}$

➡ Chemical energy into Potential energy [B].

$\bold{EXPLANATION :}$

➡ The crane uses the petrol engine to lift a heavy girder. But, here the girder is moving and also it is moving at a steady rate. So, it is the kinetic energy of girder. But, the system refers to the working of "CRANE" in which the chemical energy is generally getting converted to potential energy.

$\bold{CONCLUSION :}$

➡ It is not the main factor according to the given question that what energy conversion is happening (or, taking place) associated to the girder. Here, "SYSTEM" means "CRANE" in which chemical energy is getting converted to potential energy (KINETIC ENERGY remaining constant).