Question

The unit of energy is
(a) Watt
(b) Kilometre/hour
(c) Joule/sec
(d) Watt/sec

Answer 1

Answer:

unit of energy is joule or watt sec

Answer 2

Answer:

Joule

Explanation:

We know that energy is coming from work so the unit of work is Joule than the unit of energy is also Joule. We represent joule as J. Energy is the efficiency of a physical system to do any work. We denote energy by E.  1 joule is defined as:

When we apply 1 N force on something to displace it for 1m than some amount of energy released.

that is:

1 Joule in CGS unit:

$1 Joule = 1N force \times 1m\ displacement \\= 10 ^5 \ dyne\ force \times 100 cm\ displacement \\= 10^7 ergs$