Easy problem, but no idea how to solve it?

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To determine the stopping distance of a car traveling at 60 km/h, the discussion suggests using the equation v^2 - u^2 = 2as, where u is the initial velocity and v is the final velocity. The motorbike's stopping distance, D, is achieved with a maximum deceleration from 40 km/h to 0. By finding the deceleration (a) in terms of D, the stopping distance for the car can be calculated using the same deceleration value. The key is to relate the two velocities and apply the derived deceleration to find the new stopping distance. This approach allows for solving the problem despite the initial unknowns.
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Homework Statement


A motorbike with the velocity 40km/h is able to stop at a distance, D, when it brakes with maximal deacceleration. At what distance will a car with a velocity of 60 km/h stop?


Homework Equations




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The Attempt at a Solution


I was trying to solve it through regular equations such as at^2=distance, but there seems to be too many unknowns. Any ideas?
 
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Use v^2 - u^2 = 2as. Find a in terms of D. Here u = 40 km/hr and v = 0. Use this a and find the distance for 60 km/hr using the above equation.
 

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