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xavierengineering

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## Homework Statement

A car of mass 1000 kg is cruising at 120 km/hr. At this velocity the drag and friction forces that the engine needs to work against is equivalent to 450 N.

(i) What is the propulsive power being delivered by the engine when cruising? (4 marks)

(ii) From a velocity of 100 km/hr, the driver suddenly sees a traffic jam ahead and performs an emergency braking, resulting in locking the four wheels. Calculate the minimum braking distance required to bring the car to a full stop.

Assume the following: The coefficient of friction between the tyres and road is μ = 0.8.

Consider the weight of the vehicle to be equally distributed on each wheel while braking The drag or other friction forces are not significant in this case. g = 9.8 m/s2

## Homework Equations

D=V/2*0.8*9.81

## The Attempt at a Solution

All i know for the equation is D=V/2*0.8*9.81. However i am not sure how to implement the mass into the equation, Or if there is a different one to use.

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