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
BartSMP [9]
3 years ago
13

A hoop and a disk with uniform mass distribution have the same radius but the total masses are not known. Can they both roll dow

n a ramp without slipping and reach the bottom in the same time? And if so, what can you deduce about the relative masses?
a) The hoop and disk have the same mass.
b) The hoop is heavier, twice the mass of the disk.
c) The disk is heavier, twice the mass of the hoop.
d) They cannot reach the bottom at the same time regardless of mass.
e) The disk is lighter, three-fourth the mass of the hoop
Physics
1 answer:
ser-zykov [4K]3 years ago
5 0

Answer:

Explanation:

radius of hoop and the radius of disk is same = R

Let the mass of hoop is M and the mass of disk is M'.

As they reach the bottom of teh surface in same time so they travel equal distance thus, they have same acceleration.

The acceleration is given by

a=\frac{gSin\theta }{1+\frac{I}{MR^{2}}}

As the acceleration is same so that the moment of inertia is also same.

Moment of inertia of disk = moment of inertia of hoop

1/2 x mass of disk x R² =  mass of hoop x R²

So, mass of disk = 2 x mass of hoop

Option (c) is correct.

You might be interested in
find the time taken, if the speed of a train increased from 72 km/hr to 90 km/hr for 234 km. leave your answer in seconds
Airida [17]

Answer:

Time taken = 10400 s

Explanation:

Given:

Initial speed of the train, u=72\textrm{ km/h}=72\times \frac{5}{18}=20\textrm{ m/s}

Final speed of the train, v=90\textrm{ km/h}=90\times \frac{5}{18}=25\textrm{ m/s}

Displacement of the train, S=234\textrm{ km}=234\times 1000=234000\textrm{ m}

Using Newton's equation of motion,

v - u = at\\a=\frac{v-u}{t}

Now, using Newton's equation of motion for displacement,

v^{2}-u^{2}=2aS

Now, plug in the value of a=\frac{v-u}{t} in the above equation. This gives,

v^{2}-u^{2}=2\times \frac{v-u}{t}\times S\\(v+u)(v-u)=\frac{2(v-u)S}{t}\\t=\frac{2(v-u)S}{(v+u)(v-u)}\\t=\frac{2S}{v+u}

Now, plug in 234000 m for S, 25 m/s for v and 20 m/s for u. Solve for t.

t=\frac{2S}{v+u}\\t=\frac{2\times 234000}{25+20}\\t=\frac{468000}{45}=10400\textrm{ s}

Therefore, the time taken by the train is 10400 s.

3 0
3 years ago
Hydrogen cyanide is poisonous liquid that has a faint almond like smell. one molecule of hydrogen cyanide is made up of one hydr
Lisa [10]
"<span>H-C=N:" is the one answer among the choices given in the question that shows the correct dot diagram. The correct option among all the options that are given in the question is the fourth option or option "D". The other choices can be neglected. I hope that this is the answer that has come to your help.</span>
3 0
3 years ago
Read 2 more answers
During a tennis serve, a racket is given an angular acceleration of magnitude 150 rad/s^2. At the top of the serve, the racket h
QveST [7]

Answer:

270 m/s²

Explanation:

Given:

α = 150 rad/s²

ω = 12.0 rad/s

r = 1.30 m

Find:

a

The acceleration will have two components: a radial component and a tangential component.

The tangential component is:

at = αr

at = (150 rad/s²)(1.30 m)

at = 195 m/s²

The radial component is:

ar = v² / r

ar = ω² r

ar = (12.0 rad/s)² (1.30 m)

ar = 187.2 m/s²

So the magnitude of the total acceleration is:

a² = at² + ar²

a² = (195 m/s²)² + (187.2 m/s²)²

a = 270 m/s²

3 0
3 years ago
two long parrallel wires that are 0.30 m apart carry currents of 5.0 A and 8.0 A in the opposite direction.Find the magnitude of
Vera_Pavlovna [14]

Answer: The magnitude of force per length that each wire exert on the other wire is 2.67×10^-5 N/m.

The force is repulsive.

Explanation: Please see the attachments below

3 0
3 years ago
What is the effect that distance has on gravity?
IgorLugansk [536]
The forces of gravity between two objects are smaller when the objects are farther apart.
3 0
3 years ago
Other questions:
  • How an elastic material can no longer be elastic but plastic instead?
    6·1 answer
  • At Alpha Centauri's surface, the gravitational force between Alpha Centauri and a 2 kg mass of hot gas has a magnitude of 618.2
    6·2 answers
  • What is necessary for fossil fuels to form? oxygen forming continuously for a long period of time sunlight shining continuously
    9·2 answers
  • A particle is constrained to move along a straight line through O.
    6·1 answer
  • The magnetic field around a long, straight wire is:
    10·2 answers
  • Is 51/17 a rational number
    8·2 answers
  • How is the kintic energy of nolecules changing when the molecules move faster?
    11·2 answers
  • Which of the following is an example of the law of multiple proportions?
    9·1 answer
  • How do you calculate the total pressure?
    7·1 answer
  • a seismic wave has a measured wavelength of 0.50 km. its frequency is 27 hz. what is the velocity of the wave?
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!