{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

122_t2_soln

# 122_t2_soln - 12-2 EXAM z SOLWFIous Multiple Choice Select...

This preview shows pages 1–11. Sign up to view the full content.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 12-2. EXAM z SOLWFIous Multiple Choice. Select the best answer. No partial credit \‘J 1. What is the magnitude of the centripetal acceleration of a car in uniform circular motion traveling at a speed of 10 m/s with a radius of 20m? 2 7— 2 2 mm? d2 , 0M5) - tow/s SID/\$2 4‘ I ’ h M d) 3111/82 r 2.0M 20 M e) lm/s2 f” I 7. 4 3 SMIS 2. If you see an object move in your car and you can’t identify the source of the apparent force on the object, you are most likely in a a) non-inertial reference frame b) accelerated reference frame c inertial reference frame Cg» both a and b e) both b and c 3. According to Newton’s third law a) Forces act in pairs b) For every action force there is an equal and Opposite reaction force C) F12=-le d) [Fizl = Ilel All of the above Partial Credit Problems. Please be neat and show your work. 4. The coefficient of static friction of rubber on ice is approximately us=0.100. A 2001b woman stands on an icy sidewalk in rubber ﬂip-ﬂops on a cold Detroit day. There is a horizontal force acting on the woman to the right F. a) Draw the free body diagram of the woman clearly noting the force vectors exerted on the woman. . .1 ‘4 ,1 r-e +3 I F b) Apply Newton’s Second Law in both the x and y directions. 2‘11: 0 '3 F”f5 [IFZJFJl L,” \A: \$5: 0 v‘ WW3 0r Wei: 1 O c) From you results in part b) calculate the magnitude of the horizontal force F required for the woman to slip on the ice. F : (0400M2001bs) Now suppose the sidewalk is inclined as in the figure below and assume the horizontal force F acts down the incline: 4‘"— w = 4m -——-> d) Draw the woman’s new free body diagram, clearly noting the forces exerted on the woman. 5. H E l \ § H § 6) Apply Newton’s Second Law in both the x and y directions. f) From you results in part 6) what is the new force F required for the woman to slip in the direction down the incline? C ’2 ~14 £39: 2%] Z A? W g) You should notice that the difference between the forces in part c) and part 13 are small (within a few pounds) even though the incline is rather steep. Calculate the woman’s force due to gravity ALONG the incline. Is this force large enough for the woman to slip? F : Esme 3X ‘1 , k .— .914. : 1:: Stu/(E) ' T <- SM 3 5. A man pulls on three blocks of mass m1, m2, and m3 connected by light strings on a frictionless surface. The man exerts a force on the third block of magnitude F at an angle 6 with respect to the horizontal as in the image below (note: there are only two strings): a) Draw the free body diagram of each object clearly noting the force vectors exerted on each block: ._\ V\ ___‘l b) Apply Newton’s Second Law to each block and obtain equations for the tensions on the strings (T1 and T2), acceleration (a) and normal forces (n1, n; and n3) in both the x and y directions. c) Determine the acceleration of the system (a) in terms of m1, m2 and m3, F, and A "‘7- ~ it Frey“: (n ’W|C{ \Vl+o Z Ffowt ‘T2 ‘2‘“ (waCt -— FCOS d) What are the tensions in the strings T1 and T2 in terms of m1, m2 and m3, F, and Q , u‘bt‘VLcl CL I e) Calculate the acceleration of one block with mass m=m1+m2+m3 (the sum of the masses of all three blocks) with the same force exerted on it. Write your answer in terms of m1, m2 and mg, F, and 6! Compare this acceleration with your previous result (part 0). [Ma 2 (M‘+MZ&'V‘43\Q :. M ‘T\ X \1 ...
View Full Document

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern