1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Black_prince [1.1K]
4 years ago
8

1. Consider three objects: Object A is a hoop of mass m and radius r; Object B is a sphere

Physics
1 answer:
Zarrin [17]4 years ago
7 0

a) Object C (the disk) has the greatest rotational inertia (\frac{3}{2}mr^2)

b) Object B (the sphere) has the smallest rotational inertia (\frac{4}{5}mr^2)

Explanation:

The moments of inertia of the three objects are the following:

1) For a hoop of negligible thickness, it is

I=MR^2

where M is its mass and R its radius. For the hoop in this problem,

M = m

R = r

Therefore, its moment of inertia is

I=(m)(r)^2=mr^2

2) For a solid sphere, the moment of inertia is

I=\frac{2}{5}MR^2

where M is its mass and R its radius. For the sphere in this problem,

M = 2m

R = r

Therefore, its moment of inertia is

I=\frac{2}{5}(2m)(r)^2=\frac{4}{5}mr^2

3) For a disk of negligible thickness, the moment of inertia is

I=\frac{1}{2}MR^2

where M is its mass and R its radius. For the disk in this problem,

M = 3m

R = r

Therefore, its moment of inertia is

I=\frac{1}{2}(3m)(r)^2=\frac{3}{2}mr^2

So now we can answer the two questions:

a) Object C (the disk) has the greatest rotational inertia (\frac{3}{2}mr^2)

b) Object B (the sphere) has the smallest rotational inertia (\frac{4}{5}mr^2)

Learn more about inertia:

brainly.com/question/2286502

brainly.com/question/691705

#LearnwithBrainly

You might be interested in
When an ice cube in a glass of water melts, the water level _____. A. remains the same B. rises C. falls
tensa zangetsu [6.8K]
A.  The water level Remains the same
6 0
3 years ago
Read 2 more answers
A branch falls from a tree How fast is the branch moving after 0 28 seconds
egoroff_w [7]

Answer:

c. 2.7 m/s

Explanation:

v = a.t + v_{0}\\a = g = 9.81 m/s^{2}} \\t=0.28 s \\v_{0} = 0\\=> v = 9.81 * 0.28 = 2.74 m/s

3 0
3 years ago
Will brainlist 20 points
Len [333]

Your answer for this question is the third option.

3 0
3 years ago
Read 2 more answers
A 6.5 kg rock thrown down from a 120m high cliff with initial velocity 18 m/s down. Calculate
Olegator [25]

Answer:

See the answers below.

Explanation:

In order to solve this problem we must use the principle of energy conservation. Which tells us that the energy of a body will always be the same regardless of where it is located. For this case we have two points, point A and point B. Point A is located at the top at 120 [m] and point B is in the middle of the cliff at 60 [m].

E_{A}=E_{B}

The important thing about this problem is to identify the types of energy at each point. Let's take the reference level of potential energy at a height of zero meters. That is, at this point the potential energy is zero.

So at point A we have potential energy and since a velocity of 18 [m/s] is printed, we additionally have kinetic energy.

E_{A}=E_{pot}+E_{kin}\\E_{A}=m*g*h+\frac{1}{2}*m*v^{2}

At Point B the rock is still moving downward, therefore we have kinetic energy and since it is 60 [m] with respect to the reference level we have potential energy.

E_{B}=m*g*h+\frac{1}{2}*m*v^{2}

Therefore we will have the following equation:

(6.5*9.81*120)+(0.5*6.5*18^{2} )=(6.5*9.81*60)+(0.5*6.5*v_{B}^{2} )\\3.25*v_{B}^{2} =4878.9\\v_{B}=\sqrt{1501.2}\\v_{B}=38.75[m/s]

The kinetic energy can be easily calculated by means of the kinetic energy equation.

KE_{B}=\frac{1}{2} *m*v_{B}^{2}\\KE_{B}=0.5*6.5*(38.75)^{2}\\KE_{B}=4878.9[J]

In order to calculate the velocity at the bottom of the cliff where the reference level of potential energy (potential energy equal to zero) is located, we must pose the same equation, with the exception that at the new point there is only kinetic energy.

E_{A}=E_{C}\\6.5*9.81*120+(0.5*9.81*18^{2} )=0.5*6.5*v_{C}^{2} \\v_{c}^{2} =\sqrt{2843.39}\\v_{c}=53.32[m/s]

5 0
3 years ago
I'm confusion, can I please get help???
kotykmax [81]

Answer:

Anything below 7.0 is acidic, so the range would be 0 to 7.

Neutral is simply 7, in the middle of the scale.

Lastly, anything above 7.0 is basic or alkaline, so that would be 7 to 14.

Good luck, I hope this helps

7 0
3 years ago
Other questions:
  • Explain at least 3 primary and secondary online sources of data<br>​
    14·1 answer
  • What types of mediums are involved in the energy transfer
    12·1 answer
  • Can you do all questions
    6·1 answer
  • Does the asteroid belt revolve around the sun?
    14·1 answer
  • Find the angular momentum of a hollow spinning sphere when its angular speed is 20rad/s. The rotational inertia of the sphere is
    9·1 answer
  • 2 Points
    13·2 answers
  • a jogger does 3.45 E 6 J of work and gives off 1.67 E 6 J of heat. what is the change in her internal energy? show your work​
    9·1 answer
  • PLEASEE HELP I !!!!!!!!!!!!!!!!!!!!!!!!!
    12·1 answer
  • Một vật rắn khối lượng 1 kg, chuyển động tịnh tiến ở độ cao 2 m so với mặt đất. Vật rắn có vận
    5·1 answer
  • Kingda Ka has a maximum speed of 57.2 m/s. Determine the height of the hill on this roller coaster. Explain to get full credit,
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!