\"Zombie Shopping Cart Escape!\" Imagine you live in a world infested oraging fo

Question

"Zombie Shopping Cart Escape!" Imagine you live in a world infested oraging for supplies in an abandoned supermarket you are suddenly ambushed by a horde of zombies! Running out of the supermarket you jum roll downhill across the parking lot with an initial speed of v. The parking lot is sloped downhill at an angle with the horizontal. This is a rusty shopping cart, so friction fo negligible, but they are also not enough to prevent you from accelerating as you move along the parking lot. Let the friction force opposing your motion equal F, and the mass of the system consisting of you and the cart is m with zombies. While p into an empty shopping cart and begin to rces are NOT 1. How fast are you rolling at the end of the parking lot? Derive an expression for your speed v after traveling downhill a distance d in the shopping cart. Express your answer in terms of v, , g, d, , F, , and m 2. A standard parking space is about 2.5 m wide and this parking lot is sloped at the maximum allowable angle of 5 degrees. Find the maximum value for the coefficient of friction that will allow you roll the width of the parking lot without stopping. Write out your process in a clear, easy-to-follow manner. Here's some helpful information a. This parking lot is 20 parking spaces wide You have the mass of an average human at 60 kg The shopping cart's mass is 20 kg v.= 7 m/s Use g-10 m/s C. Once safely back at camp, you and a couple friends want to learn some more about the 3 motion of shopping carts, since jumping into one and rolling away saved your life. You decide to calculate the work done by the friction in the wheels of a shopping cart of unknown mass as it moves to the right on a horizontal surface. You have a force probe, and meter stick and a stopwatch. Describe an experimental procedure that will allow you and your friends to take the measurements needed to calculate the work done by friction.

Explanation / Answer

2. A standard parking space is about 2.5 m wide and this parking lot is sloped at the 2. maximum allowable angle of 5 degrees.

Solution:

2. given, parking space width, w = 2.5 m

angle of slope, theta = 5 deg

coeff of friciton = mu

total number of spaces, n = 20

total wodth, d = n*w = 20*2.5 = 50 m

initial speed, vo = 7 m/s

total mass, m = 60 + 20 = 80 kg

hence normal reaction force on wheels of shopping cart, assuming four wheels = N

from force balance

4N = mg*cos(theta)

assume friction force f

when

from force balance

mgsin(theta) + 4f = ma ( where a is acceleration of the system)

also

N = mu*f

hence for roling distance d, maximum value of coefficient friction has to be found

this happens when the cart comes to a final speed vf = 0 m/s at the end of the parking lot

hence

2*a*d = vf^2 - vo^2

2*a*50 = -49

a = -0.49 m/s/s

hence

80*9.81*sin(5) + mu*80*9.81*cos(5) = 80*0.49

hence

mu = 0.03734

If you like my answer please give me a thumbs UP! And sorry for any mistake done, please comment about it, I will try my best for providing well explained answers.

Thanks in advance.

Best Regards.

Related Questions

Navigate

• Browse (All)
• Browse #
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.