







A dot on a child's car wheel 
20190428 

julia pose la question : A wheel of a child’s car revolves at 10 rpm. A painted dot on the circumference of the wheel is 12 cm from the centre of rotation of the wheel. How far does the dot travel in 5 s, to one decimal place? Penny Nom lui répond. 





A rotating wheel 
20180824 

Kay pose la question : A wheel with a radius of 7 inches is rotating at 4 revolutions per second. What is the
linear speed v, in feet per second? p lui répond. 





Revolutions per minute 
20141024 

Edward pose la question : Hello; I have a 28.2 inch diameter tire; do not worry about engine RPM or gear ratios, please tell me what the RPM
of that tire is at 8 MPH and 64 MPH. Thank you.
Sincerely; Edward Penny Nom lui répond. 





Angular speed 
20140629 

andrea pose la question : a wheel having a radius of 10cm rotates such that the linear speed at its rim is 30mls.
what is the angular speed of the wheel in rpm? Penny Nom lui répond. 





Riding on a Ferris wheel 
20140321 

Claire pose la question : A Ferris wheel has a radius of 72 feet and its center is 85 feet above the ground. At the top of the Ferris wheel, Sam is in the topmost car. If the Ferris wheel makes two complete revolutions per minute, how high above the ground will Sam be after 10 seconds? Penny Nom lui répond. 





A tire rolls 100 feet in a straight line 
20140107 

Alanna pose la question : A tire has a diameter of 26 inches. If it goes 100 feet in a straight line, how many complete revolutions did it make? Penny Nom lui répond. 





Revolutions per second 
20121018 

Crystal pose la question : Suppose a car wheel is 26 inches in diameter.
a) If the tire completes one rotation, how far would the car travel?
b) If the car is traveling at 60 miles per hour, how fast is the car wheel spinning in revolutions per second? Penny Nom lui répond. 





How many rpm does a 3.5 in. diameter wheel turn at 7 miles per hour? 
20111206 

Al pose la question : how many rpm does a 3.5 in. diameter wheel turn at 7 miles per hour Penny Nom lui répond. 





Angular speed 
20101212 

Jason pose la question : 7 in. pulley traveling @ 175ft/sec. What is the rpm? Stephen La Rocque and Penny Nom lui répond. 





Angular speed 
20090804 

Mary pose la question : The engine of a sports car rotates at 5000 revolutions per minute (rpm). Calculate the angular speed of the engine in radians per second. Use 2 radians = 1 revolution. Penny Nom lui répond. 





A rolling wheel 
20090329 

Jules pose la question : How far does a wheel of radius 2 feet roll along level ground in making
300 revolutions? Penny Nom lui répond. 





The speed of a tire in revolutions per minute 
20090328 

Jules pose la question : Suppose that a tire on a car has an outer diameter of 2,5 feet. How many
revolutions per minute does that tire make when the car is travelling 60
miles per hour? (hint:first find the angular velocity in radians per minute.) Harley Weston lui répond. 





Jogging around a circular track 
20081119 

kim pose la question : Joan wants to jog 10 miles on a circular track 1/4 miles in diameter. How many times must she circle the track? Penny Nom lui répond. 





The current in a river 
20080612 

Joi pose la question : To approximate the speed of the current of a river, a circular paddle wheel with radius 4 feet is lowered into the water. If the current causes the wheel to rotate at a speed of 10 revolutions per minute, what is the speed of the current? Express your answer in miles per hour. Harley Weston lui répond. 





How many complete revolutions does each wheel make? 
20071228 

varoon pose la question : The wheels of a car are of diameter 80cm each. How many complete revolutions does each wheel make in 10 minutes when the car is travelling at a speed of 66kms per hour? Penny Nom lui répond. 





Is there a practical use for radian measure? 
20071026 

Paula pose la question : Is there a practical use for radian measure in any profession? Which professions might us radian as opposed to degree measure? Harley Weston lui répond. 





Angular speed 
20070118 

Cristina pose la question : A car is moving at a rate of 50 miles per hour, and the diameter of its wheels is 2.5 feet. a) Find the number of revolutions per minute the wheels are rotating. b) Find the angular speed of the wheels in radians per minute. Stephen La Rocque lui répond. 





What size pulley would I need? 
20061229 

Chris pose la question : If I have a motor that's spinning at 950 RPM's with a pulley that's 6in diameter with a belt running to a generator, What size pulley would I need on the generator to make it spin at 3600 RPM Penny Nom lui répond. 





A point on a bicycle rim 
20060801 

Sonu pose la question : Find the speed in m/s of a point on a bicycle rim of diameter 88cm making 200 revolutions per minute. Penny Nom lui répond. 





Angular speed 
20040201 

Rachel pose la question : A 4 inch pulley on a motor makes 1500 revolutions/minute. It is connected to an 8 inch saw blade.
a. Find the angular speed of the pulley in radians/minute
b. Find the angular speed of the saw in radians/ minute
Harley Weston lui répond. 





A rock on a string 
20031026 

A student pose la question : a rock on a 4' string is rotated at 80 rpm. what is the linear speed in feet per second? in miles per hour? Penny Nom lui répond. 





PreCalculus 
20000809 

Angela pose la question : Use absolute values to define the interval or pair of intervals on the real line.
<  ]    [ >
18 19 20 21 22 23 24 25 26
A car is moving at the rate of 50 miles per hour, and the diameter of its wheels is 2.5 feet. a) Find the number of revolutions per minute that the wheels are rotating. b) Find the angular speed of the wheels in radians per minute. Harley Weston lui répond. 





Rolling Circles 
19990912 

Craig Ellis pose la question : We have a circle of radius 3. inside the circle and tangent to the circle of radius 3 at one point is a circleof radius 1. The question is if we could roll the smaller circle around the inside of the larger circle how many revolutions would it take to get around to where we started. Chris Fisher and Walter Whiteley lui répond. 

