Question

In: Physics

12. (a) Calculate the force needed to bring a 950-kg car to rest from a speed...

12. (a) Calculate the force needed to bring a 950-kg car to rest from a speed of 90.0 km/h in a distance of 120 m (a fairly typical distance for a non-panic stop). (b) Suppose instead the car hits a concrete abutment at full speed and is brought to a stop in 2.00 m. Calculate the force exerted on the car and compare it with the force found in part (a).

Solutions

Expert Solution

Solution:

Given data

distance(s) =120m

a) Use Torricelli's equation to find the acceleration:

we know that Force formula is

Here (-) indicates the opposite direction of motion

b) Similarily Use Torricelli's equation to find the acceleration:

we know that Force formula is

Comparing it with the force found in part (a) is

Acceleration in part-(a) is a=-2.6m/s²

Acceleration in part-(b) is b=-156m/s²

Therfore acceleration is 60 times as great when compared to part-(a) to part-(b).

genius_generous answered 10 months ago

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