Need a little push. [Simple Physics Problems]

AI Thread Summary
A car accelerates uniformly at 0.7 m/s² on a circular track with a radius of 253 m. After 50 seconds, the net acceleration needs to be calculated, incorporating both tangential and centripetal components. The initial calculations led to confusion regarding the correct interpretation of acceleration types. Ultimately, the user resolved the misunderstanding, clarifying that the acceleration refers to the change in tangential velocity. The discussion highlights the importance of distinguishing between different types of acceleration in physics problems.
Emilyneedshelp
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Homework Statement


Question
A car starts from rest and uniformly increases its speed at a rate of 0.7 m/s2 on a circular track of radius R = 253 m. What is the magnitude of the car’s net acceleration after 50 s?

acen=.7m/s^2
t=50s
R=253m

Homework Equations


Equations
acen=(v^2)/r
Maybe?
ω=Δθ/Δt
a=r(Δω/Δt)

The Attempt at a Solution


√[aT^2 + aC^2]

aC=.7m/s^2
aT= r(dω/dt)√[.7(253)]=v
v=13.308m/s

v(50s)=S
S=665.4

S/r=θ
θ=2.63rad

ω=(2.63rad/50s)
ω/50=α

α=.001052rad/s^2
α(253)=aT

aT=.26616
a=√[aT^2 + aC^2]
a=.74489m/s^2

Answer is not correct, is there something wrong with my logic?
 
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The given acceleration is how fast the cars speedometer is changing. (I.e.the change in the magnitude of the tangential velocity with time).
Not acen as you've used it.
 
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Thank you, I solved it. How silly of me not to realize that.
 
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