Question

Plzz Answer...... Urgent.... Class 9 or above.... PHYSICS... Work, energy & Power...​

Answer 1

As we know,

Work done = Force * Displacement

So here the data given is,

No. of bricks = n

Mass of each brick = m

Height/displacement = h

also ⇒ Total mass = mn

From Newton's Second Law of Motion, we had concluded,

F=ma

Here acceleration is acceleration due to gravity, i.e, = 9.8 m/s²

so

Force = m * a(g)

          = mn * 9.8

          = 9.8mn

∴ WORK DONE = FORCE * DISPLACEMENT

                           = mngh

                           = 9.8mn * h

                           = 9.8mnh J (where g = 9.8)

Hope this helps ^_^