A "ten second car" is a car that can go 1/4 mile in 10 seconds starting from rest. What's the acceleration of such a ten second car in meters/second 2 ?
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I, instead, used the formula a=(v f^2-v i^2)/2s. I then plugged in 1/4 mi for s, 40 for v f, 0 for v i, solved and put it into the right unit. But I got the wrong answer. Why was that?
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How did u put in 40 for v_f??? Where did u get that???
Where did you get 50 second^2 ?
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4 0 2 . 2 5 meters = 0 + ( 2 1 × a × ( 1 0 second ) 2 )
⟹ 4 0 2 . 2 5 meters = a × 2 1 × 1 0 0 second 2
⟹ 4 0 2 . 2 5 meters = a × 5 0 second 2
⟹ 5 0 second 2 4 0 2 . 2 5 meters = a
∴ a = 8 . 0 4 5 meter/second 2
Hope that helps! :)
From s = u t + 2 1 a t 2 ,
where s = 4 1 m i l e = 4 1 ( 1 . 6 0 9 ) k m , u = 0 , a = ? , t = 1 0
substitute inside and we get 8 . 0 4 5 m / s 2
I solved it using the kinematic equation too!
but..... after putting values, answer was not found as yours..
Hello all,
Given that the s = 0.25 mile = 0.25 (1.609)(1000) = 402.25 m, u = 0 m/s,
By applying the formula,
s = ut + 0.5at^2
402.25 = 0(10) + (0.5)(a)(10)^2
50a = 402.25
a = 8.045 m/s/s...
thanks...
We know that, s=ut+(0.5)a*t^2 (here we assume u as the initial velocity , a as the accelaration and t is the time elapsed and s is the distance it has gone )
Now, the car was started from rest so u=0 and s=1/4mile =0.40225KM=402.25m and t=10s now , using the information on the formula we will get that ,
402.25=(0.5)a*t^2 =>a=8.045m/s^2
1/4 mile of a mile= 1/4*1609 meters =402.25 meters
u=0 a=? (not known) t=10 seconds s=402.25 meters
s=ut+1/2*at²
402.25= 0+1/2*a100
4.02=1/2*a
a=2*4.02
a=8.04
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If the initial velocity is v 0 , total distance traveled is d , the taken time is t and the acceleration is a , then...
d = v 0 t + 2 1 a t 2
We have the values...
v 0 = 0
d = 4 1 miles
= ( 4 1 × 1 . 6 0 9 × 1 0 0 0 ) meters
= 4 0 2 . 2 5 meters
t = 1 0 seconds
Plugging in the values, we get...
4 0 2 . 2 5 meters = 0 + 2 1 × a × ( 1 0 second ) 2
a = 5 0 second 2 4 0 2 . 2 5 meters
∴ a = 8 . 0 4 5 meter/second 2