Download the App!

Get 24/7 study help with the Numerade app for iOS and Android! Enter your email for an invite.

(1I) A cyclist intends to cycle up a $9.50^{\circ}$ hill whose verticalheight is 125 $\mathrm{m}$ . The pedals turn in a circle of diameter36.0 $\mathrm{cm} .$ Assuming the mass of bicycle plus person is 75.0 $\mathrm{kg}$ ,(a) calculate how much work must be done against gravity.(b) If each complete revolution of the pedals moves the bike 5.10 $\mathrm{m}$ along its path, calculate the average force that must be exerted on the pedals tangent to their circular path. Neglect work done by friction and other losses.

Get the answer to your homework problem.

Try Numerade free for 7 days

Like

Report

A) $9.19 \times 10^{4} \mathrm{J}$B) $547 \mathrm{N}$

Physics 101 Mechanics

Chapter 8

Conservation of Energy

Work

Kinetic Energy

Potential Energy

Energy Conservation

Moment, Impulse, and Collisions

Cornell University

Rutgers, The State University of New Jersey

University of Sheffield

University of Winnipeg

Lectures

04:05

In physics, a conservative force is a force that is path-independent, meaning that the total work done along any path in the field is the same. In other words, the work is independent of the path taken. The only force considered in classical physics to be conservative is gravitation.

04:30

In classical mechanics, impulse is the integral of a force, F, over the time interval, t, for which it acts. In the case of a constant force, the resulting change in momentum is equal to the force itself, and the impulse is the change in momentum divided by the time during which the force acts. Impulse applied to an object produces an equivalent force to that of the object's mass multiplied by its velocity. In an inertial reference frame, an object that has no net force on it will continue at a constant velocity forever. In classical mechanics, the change in an object's motion, due to a force applied, is called its acceleration. The SI unit of measure for impulse is the newton second.

04:34

(II) A cyclist intends to …

10:34

(III) A cyclist intends to…

06:21

03:06

03:04

A bicycle racer is going d…

01:15

A bicyclist travels in a c…

02:03

04:04

(III) A bicyclist can coas…

09:16

Assume a cyclist of weight…

04:27

07:28

A bicyclist is coasting s…

03:57

Okay. The first part of the problem is very straightforward to computer. Ah, work done. And that is he call to the changing gravitational potential energy of the cyclist. That is just mass times gravitational acceleration, times change in height and mass is 75 kilos. She is 9.8 meters per second and, uh, changing height is 1 25 meters. So you get 9.19 times 10 to the four jewels around 92,000 jewels. Part B is where it gets tricky. There's a lot of confusing words. They're like tangential like, you know, 10 gentle force and a complete revolution of the and the circular path center, etcetera. You've to know here that well, we can vote here. That work done again will be equal to the change in potential energy which will be us mg Delta. Why, this is not the same as Delta Wine Party. Care critical on that will be equal to force. Time's a distance. Let's call it X. Okay, just demi variable X is mean anything on dh. And so for the 10 gentle path you have, you have 10 gentle force after man. That's what you're after and acts. So that's the definition of doubting you. Our definition of change of technology is basically it's forced. Times is the product of force and distance, and so the distance traveled here will be the their comforts us the circle circumference of a circle. Okay, and so that is the circumferential distance traveled in one revolution Circumstantial distance off the of the wheels of the bike. And so that's two pi r is a circumference and that is equal to mg delta y. And so thread this down in another line here, force tangential force What we're after times two pi times radius off the wheel eyes equal to mass times acceleration due to gravity times a delta Why and that will be decided Theater debating the distance traveled by the bike are and in and when while the cycle completes one complete revolution of the two pi R is the one complete revolution part here. Okay, so what we get here is tangential forces m g d. Sign Fada over two pi r and we know all these values. Thankfully em again. 75 kilograms CI again 9.8 meters per second d is 5.1 meters and signed data is signed 9.5 degrees. You divide that by two pi r and so that's two pi times 20.18 meters for the radius of the wheel, and what you get is that 10 gentle force, and the force for after is 547 newts, and that's it.

View More Answers From This Book

Find Another Textbook

02:33

The center of mass person may be determined by an arrangement such as the on…

05:14

Review Constantsthin dielectric disk with radius has total charge distri…

02:11

The above image shows Yelena Isinbayeva (68.3 kg) at a point in her vault wh…

04:26

General Solution to Driven _ Damped Oscillator (10 points) Suppose that Eh(t…

14:49

A student holds a bike wheel and starts it spinning with an initial angular …

01:03

Consider a 24 N block on a ramp and hanging from a rope: a5 shown to the ngh…

04:41

PartWhich of the following statements are true for images formed by sphe…

05:59

Two springs are attached end to end to = box of . shown in the mass M as fig…

01:16

A coil of wire of one turn has a cross-sectional area of 0,06 m A magnetic f…

02:44

hypodermic syringe contains medicine with the density of water (as shown in …