Please help with my problems?
You are testing your brand new Ferrari Testarossa. To see how well the brakes work you accelerate to 100 miles per hour, slam on the brakes, and determine that you brought the car to a stop over a distance of 458 feet. Assuming a constant deceleration you figure that that deceleration is__ feet per second squared. (Enter a positive number.)
I trust that you don't have the courage to try this, but that night you wonder how long it would take you to stop (with the same constant deceleration) if you were moving at 200 miles per hour. Your stopping distance would be__feet. (Enter a number, not an arithmetic expression.)
You are testing your brand new Ferrari Testarossa. To see how well the brakes work you accelerate to 100 miles per hour, slam on the brakes, and determine that you brought the car to a stop over a distance of 458 feet. Assuming a constant deceleration you figure that that deceleration is__ feet per second squared. (Enter a positive number.)
I trust that you don't have the courage to try this, but that night you wonder how long it would take you to stop (with the same constant deceleration) if you were moving at 200 miles per hour. Your stopping distance would be__feet. (Enter a number, not an arithmetic expression.)
1 Answer
Car is accelerated to a velocity
Using the kinematic expression to find deceleration
#v^2-u^2=2as#
Inserting given values we get acceleration of
#(0)^2-(146.bar6)^2=2axx458#
#=>a=-(146.bar6)^2/(2xx458)#
#=>a=-23.48fs^-2# , rounded to two decimal places.
#=>"deceleration"=23.48fs^-2# , rounded to two decimal places.
For cars velocity
#v^2-u^2=2as#
#(0)^2-(293.bar3)^2=2(-23.48)s_2#
#=>s_2=(293.bar3)^2/(2xx23.48)#
#=>s_2=1832f#
