Dynamics Practice Exam #2
Problem 1
You are designing an epic playground with a slide 5 meters tall. If the coefficient of kinetic
friction between the slide and clothing is 0.5 and children shouldnt leave the slide traveling
more than 4 m/s.
What should
137.
P
If the 50kg crate starts from rest and travels a distance of 6 m
up the plane in 4 s, determine the magnitude of force P acting
on the crate. The coefficient of kinetic friction between the
crate and the ground is mk = 0.25.
30
SOLUTION
30
Kinemat
1510.
P
The 50kg crate is pulled by the constant force P. If the crate
starts from rest and achieves a speed of 10 m>s in 5 s, determine the magnitude of P. The coefficient of kinetic friction
between the crate and the ground is mk = 0.2.
30
SOLUTION
Imp
165.
Initially the motor on the circular saw turns its drive shaft at
v = 120t2>32 rad>s, where t is in seconds. If the radii of gears
A and B are 0.25 in. and 1 in., respectively, determine the
magnitudes of the velocity and acceleration of a tooth C on
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*17100.
A uniform rod having a weight of 10 lb is pin supported at A
from a roller which rides on a horizontal track. If the rod is
originally at rest, and a horizontal force of F = 15 lb is
applied to the roller, determine the acceleration of the
roller.
1643.
The crankshaft AB is rotating at a constant angular velocity
of v = 150 rad>s. Determine the velocity of the piston P at
the instant u = 30.
B
0.75 ft
0.2 ft
A
V
U
x
SOLUTION
x = 0.2 cos u + 2(0.75)2  (0 2 sin u)2
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x = 0.2 sin uu + C (0.
153.
A 5lb block is given an initial velocity of 10 ft>s up a 45
smooth slope. Determine the time for it to travel up the
slope before it stops.
SOLUTION
A Q+ B
t2
m(vx)1 +
L
t1
Fx dt = m(vx)2
5
(10) + (5 sin 45)t = 0
32.2
t = 0.439 s
Ans.
156.
A train
1422.
The 25lb block has an initial speed of v0 = 10 ft>s when it
is midway between springs A and B. After striking spring B,
it rebounds and slides across the horizontal plane toward
spring A, etc. If the coefficient of kinetic friction between
the plan
*188.
v 20 rad/s
The double pulley consists of two parts that are attached to
one another. It has a weight of 50 lb and a centroidal radius
of gyration of kO = 0.6 ft and is turning with an angular
velocity of 20 rad> s clockwise. Determine the angular
ve
172.
z
The solid cylinder has an outer radius R, height h, and is
made from a material having a density that varies from its
center as r = k + ar2, where k and a are constants.
Determine the mass of the cylinder and its moment of
inertia about the z axis.
1694.
If the roller is given a velocity of vA = 6 ft>s to the right,
determine the angular velocity of the rod and the velocity
of C at the instant shown.
C
B
6 ft
SOLUTION
v =
6 ft>s
= 1.125 rad>s = 1.12 rad>s
5.334 ft
vC = (1.125 rad>s)(3.003 ft) = 3.38
ME 361
Dynamics
Your Name _
Dynamics
Practice Exam 1
This exam should have 6 pages, with 4 problems adding up to 100 points.
The last page is blank and can be used as scrap paper for compu
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Name: _Solutions_ Alphabet: _S_
Quiz 1: Given two vectors, and ( shown below), find vector ,
where . + = Draw the vector on the diagram below.
Givens: = 4 and = 3.
85.5 = 0.12
I
Problem 1 [25 pts]
Find the force P required to accelerate the block up the hill
at 5 ft/s2.
Ph
=
0.25
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ME361
Dynamics
March 23rd 2015
YourName_
Your Seat # _
Dynamics
Exam 2.
This exam should have 4 pages, with 3 problems adding up to 100 points.
The last page is blank and can be used as scrap paper for computations and checking answers.
You may use one 3x
ME361
Dynamics
Feb. 16th 2015
Your Name _SOLUTIONS_
Your Seat # _
Dynamics
Exam 1
This exam should have 4 pages, with 3 problems adding up to 100 points.
The last page is blank and can be used as scrap paper for computations and checking answers.
You may
Quiz 12:
a V
Name:
iOil_
The yoyo shown in the figure has an outer radius, r, = 1 in. The string is
wound around an inner peg of radius, r~ = 1/4 in. The yoyo weighs 0.2 lb
and can be treated like a uniform disc or radius T0.
Find: 1. The acceleration o
Quiz 11: Name:
_
The rearwheel drive truck is accelerating to the
left while towing the boulder B.
1
a). Draw the freebodykinetic diagram for the truck.
include all forces and accelerations.
t
r
C
~tt
1
A],
b). Express with an equation how will you det
Quiz 10: Name:
SOLUTIONS
The wheel is rolling to the right.
It travels at a constant speed of
4 m/s. Find the velocity of
points C and point D.
Use the velocity of the wheel ( = 4 ) to find .
=
4
=
Point B is an instantaneous center so I can reference
Quiz 11a: Name: _SOLUTIONS_
In the following diagram, wheel C rolls to the right without slip.
a). Draw the velocity vector (direction only) for point C.
b). Draw the velocity vector (direction only) for point B.
c). Find and label the instantaneous cente
Quiz 9: Name: _Solution_
The bucket is hoisted by the rope that
wraps around a drum wheel. The
angular displacement of the wheel is
= + 15( rad), where is in seconds.
(a) How far has the bucket moved from 0 = to 4= s?
1
y = 57.0 = + 15 = 69
2
(b) Deter