Hi, this is my first post and i'm a bit rusty will mechanics so I need help with two questions i've come across(adsbygoogle = window.adsbygoogle || []).push({});

Firstly on the question sheet I am given:

a = F/m and w = mg and the static friction and kinetic friction equations

also v[tex]^{2}[/tex] = v[tex]^{2}_{0}[/tex] + 2a[tex]\Delta[/tex]x

How do I do these:

1. The coefficient of friction between the bed of a truck and a box is 0.30.

The truck is moving at 80km/h horizontally.

What is the least distance in which the truck can stop if the box is not to slide?

2. A car travelling at 30m/s on a horizontal road brakes suddenly to avoid hitting a pedestrian. What is the stopping distance if

a) The car has ABS brakes, wheels do not slip ([tex]\mu[/tex]s=0.5)

b) The car has no ABS, wheels lock ([tex]\mu[/tex]k=0.3)

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# Homework Help: Coefficient of Friction Questions I cant do

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