Explain why:- it is easier to pull a lawn mower than to push it.

Explanation

Let force P is applied when roller is pulled or pushed. Force P can be resolved in two components `Pcostheta` and `Psintheta` as shown in the figures.

In case of pulling a lawn roller normal rection, R = `Mg - P sin theta`
`:.` Kinetic friction
`F_1 = mu_k R = ( Mg - P sin theta)` ...(i)
Form equation (i) and (ii), it is clear that
It means, it easier to pull than to push a lawn roller.
In case pushing a lawn roller
Here normal reaction, `R = Mg + P sin theta`
`:. ` Kinetic friction
`F_2 = mu_kR = mu_k (Mg + P sin theta) ....(ii) `
`F_1 lt F_2`