Question

4. வறண்ட நிலமும் வளமான நிலமும் பேசுவதாக உரையாடல் உருவாக்குக.
வறண்ட நிலம்
வளமான நிலம்
வறண்ட நிலம்
வளமான நிலம்​

Answer 1

Answer:

The concept of work-energy theorem is often misunderstood. I'll try to explain it.

Firstly, let us understand what work in physics exactly means. Work is the displacement caused by an applied force on a body. In vector representation, W=F.S, which means that work(a scalar) equals the dot product of force (a vector) and displacement (also a vector). Work is actually a quantity that is analogous to energy. Work can be, informally speaking, thought of as a form of energy, according to the first law of thermodynamics. Thus, it can be added to or subtracted from a body's energy value.

According to the work-energy theorem, the work done on a body is equal to the total change in its mechanical energy.

If the body is acted upon by non-conservative forces, we can say that the work done on it is equal to the change in its kinetic energy. If the body is in a conservative force field, then the change in potential energy as well as kinetic energy is equal to the work done by all external and non-conservative forces. Here it is important to note that work done by conservative forces is defined as potential energy , but with a negative sign. The reason is that if we consider:

Change in KE= Work by conservative forces+ Work by non-conservative forces+Work by external forces

Or,

Change in KE-Work by conservative forces= Work by non-conservative forces+Work by external forces

Or,

Change in KE+ Change in PE=Work by non-conservative forces+Work by external forces