School of Mathematics and Statistics
Junior
The University of Sydney
spcr

Measuring Speed Quiz

Last unanswered question  Question  Next unanswered question
 

Web resources available

 
 
This quiz tests the work covered in Lecture 7 and corresponds to Section 2.1 of the textbook Calculus: Single and Multivariable (Hughes-Hallett, Gleason, McCallum et al.).
There is a web quiz at Wiley. It is the same quiz for each section of Chapter 2 and you should probably wait until the end of lecture 9 before you attempt it.

Be aware that it doesn’t seem to accept the written answers so you will have to check whether your answers are correct when they print the correct answer. Questions 11 and 12 were illegible on 14/11/05.

The Mathematics Learning Centre has a booklet on differentiation Introduction to Differential Calculus which covers all of the topics for the next few lectures. In particular, Chapter 1 of the booklet covers this topic.

The site http://www.math.uncc.edu/~bjwichno/fall2004-math1242-006/Review_Calc_I/lec_deriv.htm covers some of the material in Section 2.1-2.3


 

Question 1

 
 
The distance, s,  a car has travelled from its starting point on a trip is shown in the table below as a function of time, t,  since the trip started.

t  (hours) 0   1  2  3  4  5
s  (km)  0 45 135220300400
Which of the following is the average velocity between t = 1  and t = 3 ?
a) 80 km/hr   b) 88.3 km/hr
c) 87.5 km/hr   d) 85 km/hr

 

Not correct. Choice (a) is false.
Try again, this is the average velocity over the whole trip.
Not correct. Choice (b) is false.
Try again, this is the average velocity between t = 2  and t = 5 .
Your answer is correct.
Average velocity = 220---45=  175= 87.5
   2       2  km/hr.
Not correct. Choice (d) is false.
Try again, this is the average velocity between t = 2  and t = 3 ?
 

Question 2

 
 
In a time of t  seconds, a particle moves a distance of s  metres from its starting point, where s = 3t2 + 4  .
Which one of the following sets of statements is correct?
a) The average velocity between t = 1  and t = 1 + h
at h = 0.1  is 6.3,
at h = 0.01  is 6.03 ,
at h = 0.001  is 6.003
and we estimate the instantaneous velocity at of the particle at t = 1  to be 6 m/sec.
b) The average velocity between t = 1  and t = 1+ h
at h = 0.1  is 6.1,
at h = 0.01  is 6.01 ,
at h = 0.001  is 6.001
and we estimate the instantaneous velocity at of the particle at t = 1  to be 6 m/sec.
c) The average velocity between t = 1  and t = 1 + h
at h = 0.1  is 3.1,
at h = 0.01  is 3.01 ,
at h = 0.001  is 3.001
and we estimate the instantaneous velocity at of the particle at t = 1  to be 3 m/sec.
d) The average velocity between t = 1  and t = 1 + h
at h = 0.1  is 76.1,
at h = 0.01  is 706.01 ,
at h = 0.001  is 7006.001
and we cannot estimate the instantaneous velocity at of the particle at t = 1.

 

Your answer is correct.
The average velocity =3(1 + h)2 + 4- 7  3+ 6h + 3h2 + 4- 7
------h--------= --------h---------= 3h+ 6
Not correct. Choice (b) is false.
Try again, you may not have expanded 3(1 +h)2  correctly.
Not correct. Choice (c) is false.
Try again, you may not have expanded 3(1 +h)2  correctly.
Not correct. Choice (d) is false.
Try again, you seem to have forgotten to substitute t = 1  into the formula.
 

Question 3

 
 
Consider the graph below
PIC
At which labelled points does the graph have negative slope?
a) A, B, D.   b) B, C, E, F.
c) A, D.   d) C, E, F.

 

Not correct. Choice (a) is false.
Try again, B has zero slope which we do not consider to be negative.
Not correct. Choice (b) is false.
Try again, all of these slopes are greater than, or equal to zero.
Your answer is correct.
The graph is decreasing as x  increases at these points so the slope is negative.
Not correct. Choice (d) is false.
Try again, these slopes are all positive.
 

Question 4

 
 
Using algebra which of the following evaluates the limit             3
lim  (2-+-h)---8
h→0     h  correctly?
a)     (2-+-h)3---8
lhim→0     h     = hli→m0(h + 4) = 4.    b) lim (2+-h)3 --8 = lim (h2 + 6h + 12) = 12.
h→0      h       h→0
c)  lim (2+-h)3 --8 = lim (h2 + 8h+ 10) = 10 .
h→0     h        h→0    d)           3
 lim (2+-h)---8 = lim (h2 + 6h+ 12) = 17.
h→0      h       h→0

 

Not correct. Choice (a) is false.
Try again, you seem to have expanded (2+ h)3  incorrectly.
Your answer is correct.
 lim (2+-h)3 --8 = lim 8-+-12h+-6h2 +-h3---8= lim(h2 +6h + 12) = 12.
h→0     h        h→0         h            h→0
Not correct. Choice (c) is false.
Try again, you seem to have expanded (2+ h)3  incorrectly.
Not correct. Choice (d) is false.
Try again, you seem to have substituted h = 1  into the formula instead of h = 0.