Answer to Question #130854 in Classical Mechanics for John

Question

A mass of 80 kg slides down a frictionless inclined plane which is 21 m high and 80 m long. Calculate the work done by gravity as the mass slides from the top to the bottom of the incline

Answer 1

solution:-

given data are

mass of block(m)=80 kg

height of inclined plane(h)=21 m

length of inclined plane=80 m

figure can be drawn like this

work done by a force can be given as

$W=F.d$

force F=mg

d=displacement in direction of force

$W=mgh$

(h is the displacement in the direction of force)

by putting the value of m, g and h in above equation

$W=80\times 9.8\times21$

$W=16464 J$

$\fcolorbox{red}{aqua}{$W=16.464KJ$}$

therefore work done by the gravity when block slide down from top to bottom on

inclined plane is 16.464 K J.