1 Problems 1-3 Slide 1 / 30 A disc rotates about an axis...
Transcript of 1 Problems 1-3 Slide 1 / 30 A disc rotates about an axis...
Slide 1 / 30
1 Problems 1-3A disc rotates about an axis through its center according to the relation θ (t) = t4/4 – 2t
Determine the angular velocity of the disc at t= 2 s
A 2 rad/s
B 4 rad/s
C 6 rad/s
D 8 rad/s
E 10 rad/s
Slide 2 / 30
2 Problems 1-3A disc rotates about an axis through its center according to the relation θ (t) = t4/4 – 2t
Determine the angular acceleration of the disc at t = 3 s. A 9 rad/s2
B 27 rad/s2
C 6 rad/s2
D 25 rad/s2
E 2 rad/s2
Slide 3 / 30
3 Problems 1-3A disc rotates about an axis through its center according to the relation θ (t) = t4/4 – 2t
Determine the linear speed of a point on the disc 50 cm from the center at t = 1 s.
A -0.5 m/sB -1 m/s
C 1 m/s
D 1.5 m/s
E 4 m/s
Slide 4 / 30
4 Problems 4-5A hula-hoop with moment of inertia is rotating with an angular velocity of ω (t) = 3t2 – 1.
Through what angular displacement will the hula-hoop move in the first 5 s? A 30 radB 45 rad
C 90 rad
D 100 radE 120 rad
Slide 5 / 30
5 Problems 4-5A hula-hoop with moment of inertia is rotating with an angular velocity of ω (t) = 3t2 – 1.
What is the linear acceleration of the hula-hoop at t= 3 s at a point of R = 2 m? A 3 m/s2
B 10 m/s2
C 18 m/s2
D 36 m/s2
E 48 m/s2
Slide 6 / 30
6 Problems 6-7A rod is pivoted about its center and rotating at 2 rad/s. It increases uniformly in angular velocity to 14 rad/s in 3 s. Find the angular acceleration over the 3 s period. A 2 rad/s2
B 4 rad/s2
C 6 rad/s2
D 8 rad/s2
E 14 rad/s2
Slide 7 / 30
7 Problems 6-7A rod is pivoted about its center and rotating at 2 rad/s. It increases uniformly in angular velocity to 14 rad/s in 3 s. Find the angular displacement over the 3 s period. A 24 radB 48 rad
C 3 radD 2 radE 12 rad
Slide 8 / 30
8 Problems 8-9A bicycle wheel with a radius of 40 cm is spinning at a certain instance with an angular speed of 10 rad/s. The angular speed is increasing at 80 rad/s2.
At this instant, find the tangential component of the bicycle’s acceleration.
A 8 m/s2
B 2 m/s2
C 32 m/s2
D 25 m/s2
E 40 m/s2
Slide 9 / 30
9 Problems 8-9A bicycle wheel with a radius of 40 cm is spinning at a certain instance with an angular speed of 10 rad/s. The angular speed is increasing at 80 rad/s2.
At this instant, find the centripetal component of the bicycle’s acceleration.
A 12 rad/s2B 24 rad/s2C 32 rad/s2D 36 rad/s2E 40 rad/s2
Slide 10 / 30
10 Problems 10-12A record on a turntable is spinning and coming to rest. At t=0s the angular velocity of the disc is 20 rad/s and its angular acceleration is constant at -5 rad/s2. How long does it take for the record to come to rest?
A 2 s
B 4 s
C 8 s
D 10 s
E 12 s
Slide 11 / 30
11 Problems 10-12A record on a turntable is spinning and coming to rest. At t=0s the angular velocity of the disc is 20 rad/s and its angular acceleration is constant at -5 rad/s2. What is the disc’s angular velocity at t = 0.5 s? A 10 rad/s
B 15 rad/s
C 16.5 rad/s
D 17.5 rad/s
E 19.5 rad/s
Slide 12 / 30
12 Problems 10-12A record on a turntable is spinning and coming to rest. At t=0s the angular velocity of the disc is 20 rad/s and its angular acceleration is constant at -5 rad/s2. What is the angular displacement of the record through t = 2s? A 30 radB 15 rad
C 40 rad
D 50 radE 25 rad
Slide 13 / 30
13 A tire is rolling with an initial angular velocity of 10 rad/s. It decelerates with an angular acceleration of 5 rad/s2 and comes to rest. What is the net angular displacement of the wheel?
A 5 radB 10 rad
C 20 rad
D 25 radE 30 rad
Slide 14 / 30
14 Find the displacement of a wheel if the radius is 8 m and the angular displacement of the wheel is 3 rad.
A 3 m
B 9 m
C 24 m
D 36 m
E 48 m
Slide 15 / 30
15 An angular acceleration of a bowling ball is given by α (t) = 2t + 3. If the object starts from rest what is the angular velocity of the bowling ball at t = 4 s?
A 12 rad/s
B 8 rad/s
C 16 rad/s
D 28 rad/s
E 32 rad/s
Slide 16 / 30
16 If an object starts from rest and accelerates with a constant angular acceleration of 6 rad/s2 what is the angular velocity at 3 s?
A 9.5 rad/s
B 18 rad/s
C 13 rad/s
D 27 rad/s
E 10.5 rad/s
Slide 17 / 30
17 The angular acceleration of an object is given by α (t) = 3t + 2. If the object starts from rest what is the angular displacement of the object at the end of t=3s?
A 9.5 rad
B 22.5 rad
C 27 rad
D 12 radE 5 rad
Slide 18 / 30
18 Questions 18-20An object has an initial angular velocity of zero and begins to accelerate. Its new angular velocity is given by the equation, ω=4t2-5t.
What is the angular velocity of the object at t=4s A 44 rad/s
B 64 rad/s
C 84 rad/s
D 92 rad/s
E 104 rad/s
Slide 19 / 30
19 Questions 18-20An object has an initial angular velocity of zero and begins to accelerate. Its new angular velocity is given by the equation, ω=4t2-5t.
What is the angular acceleration of the object at time t=3s?
A 5 rad/s2
B 11 rad/s2
C 19 rad/s2
D 24 rad/s2
E 29 rad/s2
Slide 20 / 30
20 Questions 18-20An object has an initial angular velocity of zero and begins to accelerate. Its new angular velocity is given by the equation, ω=4t2-5t.
What is the angular displacement that the object covered in time t=3s A 6.25 radB 13.5 rad
C 17 rad
D 22 radE 27.5 rad
Slide 21 / 30
21 Questions 21-26A car whose tire has a radius of .5m has an angular velocity given by 3t2-5t+20.
Find the angular velocity of the tire at t=2s. A 14 rad/s
B 22 rad/s
C 24 rad/s
D 27 rad/s
E 30 rad/s
Slide 22 / 30
22 Questions 21-26A car whose tire has a radius of .5m has an angular velocity given by 3t2-5t+20.
Find the velocity of the wheel at time t=2s. A 7 m/s
B 11 m/s
C 12 m/s
D 13.5 m/s
E 15 m/s
Slide 23 / 30
23 Questions 21-26A car whose tire has a radius of .5m has an angular velocity given by 3t2-5t+20.
What angular distance does the tire sweep through in 4 seconds? A 85 radB 96 rad
C 104 rad
D 108 radE 110 rad
Slide 24 / 30
24 Questions 21-26A car whose tire has a radius of .5m has an angular velocity given by 3t2-5t+20.
What is the horizontal distance that the object traveled? A 26 m
B 52 m
C 66 m
D 72 m
E 83 m
Slide 25 / 30
25 Questions 21-26A car whose tire has a radius of .5m has an angular velocity given by 3t2-5t+20.
Find the angular acceleration of the tire at t=1 second. A .25 rad/s2
B .5 rad/s2
C .75 rad/s2
D 1 rad/s2
E 1.25 rad/s2
Slide 26 / 30
26 Questions 21-26A car whose tire has a radius of .5m has an angular velocity given by 3t2-5t+20.
Find the centripetal acceleration of the tire at t=2s. A 121 m/s2
B 242 m/s2
C 308 m/s2
D 347 m/s2
E 428 m/s2
Slide 27 / 30
27 An object has an initial angular velocity of 5 rad/s and undergoes an angular acceleration of 15 rad/s2, what is the final angular velocity after 3 seconds.
A 25 rad/s
B 35 rad/s
C 50 rad/s
D 65 rad/s
E 80 rad/s
Slide 28 / 30
28 An object has a final angular velocity of 25 rad/s and sweeps through 80 rads with an angular acceleration of 2.5 rad/s2. What is the initial angular velocity?
A 15 rad/s
B 25 rad/s
C 32 rad/s
D 48 rad/s
E 52 rad/s
Slide 29 / 30
29 An object has an initial angular velocity of 5 rad/s and undergoes a constant angular acceleration of -0.1 rad/s2. What is the net distance it sweeps through in 3 seconds?
A 12.25 radB 14.55 rad
C 16.25 rad
D 19.25 radE 21.5 rad
Slide 30 / 30
30 A ball is attached to a string and rotates in a circle. If it takes 1 second to complete 1 revolution what is the angular speed of the ball?
A 3.14 rad/s
B 6.28 rad/s
C 9.42 rad/s
D 12.56 rad/s
E 15.75 rad/s