Does Opposite Acceleration Decrease Car Speed?

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When a car experiences acceleration that is directed opposite to its motion, it results in negative acceleration, leading to a decrease in speed. The discussion highlights that even if the instantaneous acceleration is increasing, its opposite direction means the car's velocity will decline over time. This scenario is likened to applying brakes with increasing force while the car is in motion. Proper interpretation of the problem's wording is crucial for understanding the dynamics involved. Overall, the car's speed decreases due to the opposing acceleration.
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A person is driving a car down a road. The instantaneous acceleration is increasing with time, but is directed opposite the direction of the car's motion. what is the speed of the car? is it decreasing because the acceleration is opposite with the car's motion? Please Help. Thank you
 
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Acceleration is change in velocity over time, so if it is in the opposite direction to the cars motion, then the acceleration would be negative.

If you had a negative acceleration, what would you expect to happen to the velocity as time went on?
 
The statement is a little vague. Is the acceleration directed opposite of the car's motion, or is the increase in the acceleration directed opposite of the car's motion?
 
The instantaneous acceleration in increasing, it's not constantly increasing and it's opposite direction of the car's motion. So I thought that the speed is decreasing since the acceleration is opposite with the car's motion.
 
chrissy9624 said:
A person is driving a car down a road. The instantaneous acceleration is increasing with time, but is directed opposite the direction of the car's motion. what is the speed of the car? is it decreasing because the acceleration is opposite with the car's motion? Please Help. Thank you

That's sound reasoning. Sometimes the hardest part of a problem lies in interpreting the wording :smile:

The situation described is analogous to stepping on the brakes with increasing force (while the car is in motion, of course).

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P.S. chrissy9624, next time please make use of the posting template provided when you start a thread. Homework Help posts need to meet a certain format, content, and effort level. You barely met the last two criteria with the above :smile:
 
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