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 'Errors and significant figures'

I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
View full post »
Thread 'A cylinder connected to a hanging mass'

Thread 'A cylinder connected to a hanging mass'

Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
View full post »

Similar threads

Are suvat equations valid in 2 dimensional motion for constant acceleration?
Replies
5
Views
1K
Where can I find Similar Kinematics Questions?
Replies
2
Views
1K
Problem with Dynamic blocks on a fixed inclined plane
Replies
10
Views
2K
Projectile motion problem – determining initial velocity of throw
Replies
3
Views
2K
Kinematic Problem w/ Parabola: Solving w/ KE Theorem?
Replies
25
Views
3K
Projectile motion, initial height and range given, find initial velocity
Replies
8
Views
1K
Kinematics, curvilinear motion (a couple of questions)
Replies
30
Views
2K
Solve Kinematic Problems with Graphs?
Replies
5
Views
2K
How many equations for kinematics?
Replies
4
Views
2K
Why is there no acceleration in the southern/y direction?
Replies
10
Views
1K

Hot Threads

Recent Insights

Back
Top