Concept explainers
(a)
Distance required to bring the car to a stop when the car is skidding.
(a)
Answer to Problem 46P
The distance is
Explanation of Solution
According to Newton’s laws
Here
The acceleration is in the opposite direction from the velocity, and so has a negative sign.
Then the distance travelled is,
Here
Conclusion:
Substitute
The distance is
(b)
Distance required to bring the car to a stop when the wheels are not locked up.
(b)
Answer to Problem 46P
The distance is
Explanation of Solution
In the case of non-skidding, the distance covered would be
Here
Conclusion:
Substitute
The distance is
(c)
The distance the wheels go if the wheels lock into a skidding stop.
(c)
Answer to Problem 46P
The distance is
Explanation of Solution
The skidding car goes by
Or,
The ratio implies that at any speed, the skidding car will have
The stopping distance with antilock brakes is shorter.
Conclusion:
The distance is
(d)
Whether antilock brake makes big difference in emergency stops.
(d)
Answer to Problem 46P
The stopping distance of cars with antilock brakes are significantly shorter around
Explanation of Solution
Antilock brakes generally offers improved vehicle control and decreases stopping distances on dry and some slippery surfaces, on loose gravel or snow-covered surfaces. They significantly decrease braking distance, while still improving steering control.
Conclusion:
Therefore, the stopping distance of cars with antilock brakes are significantly shorter around
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Chapter 3 Solutions
College Physics, Volume 1
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