2 Problems i need hlep with, Acceleation and Time

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To determine how long it takes for a car to cross a 45m intersection while accelerating from rest at 14.3 m/s², the first kinematic equation can be applied: Xf = Xi + Vi*t + (a*t²)/2. For the second problem, where a car accelerates from rest to 495 km/h in 16 seconds, the average acceleration can be calculated using the formula a = (Vf - Vi) / t, converting units as necessary. The discussion emphasizes the importance of understanding kinematic equations to solve these physics problems effectively. The user expresses a lack of equations in their notes but is guided to utilize the available formulas. Mastery of these equations is crucial for solving motion-related problems in physics.
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1. ok so i have my physics packet and i need help bad. the problem is...
How long does it take a car to cross a 45m wide intersction after the light turns green if it accelerates from rest to constant 14.3 m/sec^2
Find T

and

A Car accelerates along a straight road from rest to 495 km/h in 16 sec. what is the magnitude of its average acceleration
Find a= ? km per hour/ sec
Find a= ? m/s^2
2.i don't have much equations for this problem in any of my notes
 
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Maury_702 said:
1. ok so i have my physics packet and i need help bad. the problem is...
How long does it take a car to cross a 45m wide intersction after the light turns green if it accelerates from rest to constant 14.3 m/sec^2
Find T

and

A Car accelerates along a straight road from rest to 495 km/h in 16 sec. what is the magnitude of its average acceleration
Find a= ? km per hour/ sec
Find a= ? m/s^2
2.i don't have much equations for this problem in any of my notes

Do you the two velocity and position kinematic equations?

Xf=Xi+Vi*t+(a*t2)/2

Vf=Vi+a*t

Xf=final position
Xi=initial position
Vf=final velocity
Vi=initial velocity
t=time
a=acceleration
 
i do have the 2nd one but i don't see how they can help me
 
Try and use the first equation for your first problem.
You don't need more then that
 
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