Kinematics and One Dimensional Motion

AI Thread Summary
The discussion centers on whether deceleration can be assumed to be the same in different instances of one-dimensional motion. It explores the idea that the acceleration of a car during braking might be independent of its speed. A participant concludes that they have resolved their query, stating the answer is D/9. The conversation reflects a focus on the principles of kinematics and the implications of speed on deceleration. Overall, the thread emphasizes understanding the relationship between speed and braking in one-dimensional motion scenarios.
ayans2495
Messages
58
Reaction score
2
Homework Statement
A car is travelling at 120 km/h, when the driver sees a herd of cows on the road ahead and slams on the brakes. The performance of the car’s brakes is such that the car comes to a stop in a distance D meters. Assuming that the acceleration of the car under braking is independent of the car’s speed, what distance would the car require to come to a stop if it were travelling at 40 km/h instead?
Relevant Equations
v=d/t, x=ut+1/2at^2
Would we assume that the deceleration of both instance are the same?
 
Physics news on Phys.org
ayans2495 said:
Would we assume that the deceleration of both instance are the same?
I think that's what the question is trying to say, by
Assuming that the acceleration of the car under braking is independent of the car’s speed,
 
hmmm27 said:
I think that's what the question is trying to say, by
Don't worry, I've figured it out. It's D/9. Thank you though.
 
ayans2495 said:
Don't worry, I've figured it out. It's D/9. Thank you though.
Not going to ; cheers.
 
Thread 'Voltmeter readings for this circuit with switches'
TL;DR Summary: I would like to know the voltmeter readings on the two resistors separately in the picture in the following cases , When one of the keys is closed When both of them are opened (Knowing that the battery has negligible internal resistance) My thoughts for the first case , one of them must be 12 volt while the other is 0 The second case we'll I think both voltmeter readings should be 12 volt since they are both parallel to the battery and they involve the key within what the...
Thread 'Struggling to make relation between elastic force and height'
Hello guys this is what I tried so far. I used the UTS to calculate the force it needs when the rope tears. My idea was to make a relationship/ function that would give me the force depending on height. Yeah i couldnt find a way to solve it. I also thought about how I could use hooks law (how it was given to me in my script) with the thought of instead of having two part of a rope id have one singular rope from the middle to the top where I could find the difference in height. But the...
Back
Top