Question

(b) bo termine the instantane os decimal places in your answer.) elocity or the ear at t 、75, using time intervals of 0 40 s, o 20 s, and 0.10 s (in order to better see the limiting process keep at least three t65 68 n iO% of the correct value. This may be due to error, or you could have a mistake in your calculation. Carry out all to at least four-digit accuracy to minimize roundoff error, m/s (Use the interval from t4.50 s to 4.90 s) This may be due to roundoff error, or you could have a mistake in your calculation. Carry out al 0.20 Your response is within 10% of the correct value. to at least four-digit accuracy to minimize roundoff error, m/s (Use due to the interval from t 4.60 s to 4.80 s.) 0.10s Your response is to at least four-digit accuracy to minimize roundoff error, m/s (Use the interval from t 4.65 s to 4.75 s.) 10% of the correct value. This may be due to roundoff error, or you could have a mistake in your calculation. Carry out all (c) Compare the average velocity during the first 4.7 s with the results of part (b). The average velocity of 47 Your response differs fr

A race car moves such that its position fits the relationship

x = (5.5 m/s)t + (0.85 m/s³)t³

where x is measured in meters and t in seconds.

Answer 1

Position of car

r5.5t +0.85t

b)

, from
tỉ 4.5s
to
to 4.9 s

At
tỉ 4.5s
,
r1 = 5.5(4.5) + 0.85(4.5)3-102.206 m

At
to 4.9 s
,
T2 = 5.5(4.9) + 0.85(4.9) 126.952 m

Instantaneous velocity is

-----

, from
t1-4.6s
to
to 4.8 s

At
t1-4.6s
, $x_1=5.5(4.6)+0.85(4.6)^3=108.036,m$

At
to 4.8 s
, $x_2=5.5(4.8)+0.85(4.8)^3=120.403,m$

Instantaneous velocity is

---------

, from $t_1=4.65,s$ to $t_2=4.75,s$

At $t_1=4.65,s$, $x_1=5.5(4.65)+0.85(4.65)^3=111.038,m$

At $t_2=4.75,s$, $x_2=5.5(4.75)+0.85(4.75)^3=117.221,m$

Instantaneous velocity is

----------

c)

Average velocity during first $t=4.7,s$ is

$v_{avg}=rac{5.5(4.7)+0.85(4.7)^3}{4.7}=rac{114.10}{4.7}=24.28,m/s$ is much less than instantaneous velocity.