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
son4ous [18]
3 years ago
13

A 2.0 kg block is released from rest at the top of a curved incline in the shape of a quarter of a circle of radius R = 3.0 m. T

he block then slides onto a horizontal plane where it finally comes to rest a distance D from the beginning of the plane. The curved incline is frictionless, but there is a coefficient of friction, μ = 0.5, on the horizontal plane. Determine the velocity of the box at maximum kinetic energy
Physics
1 answer:
Zigmanuir [339]3 years ago
3 0

The block has maximum kinetic energy at the bottom of the curved incline. Since its radius is 3.0 m, this is also the block's starting height. Find the block's potential energy <em>PE</em> :

<em>PE</em> = <em>m g h</em>

<em>PE</em> = (2.0 kg) (9.8 m/s²) (3.0 m)

<em>PE</em> = 58.8 J

Energy is conserved throughout the block's descent, so that <em>PE</em> at the top of the curve is equal to kinetic energy <em>KE</em> at the bottom. Solve for the velocity <em>v</em> :

<em>PE</em> = <em>KE</em>

58.8 J = 1/2 <em>m v</em> ²

117.6 J = (2.0 kg) <em>v</em> ²

<em>v</em> = √((117.6 J) / (2.0 kg))

<em>v</em> ≈ 7.668 m/s ≈ 7.7 m/s

You might be interested in
The energy of an electromagnetic wave changes proportionally to which
ozzi

Answer:

D. Frequency

Explanation:

The energy of an  electromagnetic wave is proportional to frequency, mathematically it is expressed as;

E ∝ f

E = hf

where;

h is Planck's constant = 6.626 x 10⁻³⁴ Js

The equation above can also be expanded to;

E = hf = h \frac{c}{\lambda}

where;

c is speed of light = 3 x 10⁸ m/s

λ is the wavelength of the electromagnetic wave

Since the speed of light is constant, we can conclude that the energy of the electromagnetic wave is directly proportional to its frequency and inversely proportional to its wavelength.

Therefore, the correct option for direct proportionality is FREQUENCY

8 0
3 years ago
Jill is pushing a box across the floor. Which represents the upward force perpendicular to the floor?
Georgia [21]

Answer:

When Jill is pushing a box across a floor, it represents the upward motion and it is natural force is applied.

So it is represented as FN and normal force takes place in considering the force perpendicular to the floor.

It seems to support that forced applied on an object when the object is in contact with other.

Explanation:

5 0
3 years ago
HELPP ME IN PHYSICS +15 POINTS!! <br> But a right answer not links or I’ll report. -_-
frozen [14]

The answer shud be 31 . 14m

8 0
3 years ago
A less massive moving object has an elastic collision with a more massive object that is not moving. Compare the initial velocit
stepladder [879]

Assume that the small-massed particle is m and the heavier mass particle is M.

Now, by momentum conservation and energy conservation:

   mv = mv_{m} + Mv_{M}

   mv^{2} = mv^{2}_{m} + Mv^{2}_{M}

Now, there are 2 solutions but, one of them is useless to this question's main point so I excluded that point. Ask me in the comments if you want the excluded solution too.

   v_{m} = v\frac{m - M}{m + M}\\\\\\v_{M} = v\frac{m + M}{m + M}\\

So now, we see that v_{m} < 0 and v_{M} > 0. So therefore, the smaller mass recoils out.

Hope this helps you!

Bye!

7 0
3 years ago
A block of mass m=1.2 kg is held at rest against a spring with a force constant k=730N/m. Initially the spring is compressed a d
igor_vitrenko [27]

Answer:

Explanation:

potential energy of compressed spring

= 1/2 k d²

= 1/2 x 730 d²

= 365 d²

This energy will be given to block of mass of 1.2 kg in the form of kinetic energy .

Kinetic energy after crossing the rough patch

= 1/2 x 1.2 x 2.3²

= 3.174 J

Loss of energy

= 365 d² - 3.174  

This loss is due to negative work done by frictional force

work done by friction = friction force x width of patch

= μmg d ,   μ = coefficient of friction , m is mass of block , d is width of patch

= .44 x 1.2 x 9.8 x .05

= .2587 J

365 d² - 3.174   = .2587

365 d² = 3.4327

d² = 3.4327 / 365

= .0094

d = .097 m

= 9.7 cm

If friction increases , loss of energy increases . so to achieve same kinetic energy , d will have to be increased so that initial energy increases so compensate increased loss .

5 0
3 years ago
Other questions:
  • Two vectors A and B are added together to form a vector C. The relationship between the magnitudes of the vectors is given by A
    6·1 answer
  • What does Einstein's famous equation for nuclear energy, E = mc^2, mean?
    10·1 answer
  • Why have fossil fuels become our primary energy resource
    12·2 answers
  • A thin film soap bubble (n=1.35) is floating in air. If the thickness of the bubble wall is 300nm, which of the following wavele
    15·1 answer
  • Which of the following best describes images formed by a convex mirror?
    12·2 answers
  • Bill forgets to put his car in park and it starts rolling west. When it is moving at a speed of 3.5 m/s, it collides with Tanya'
    14·2 answers
  • Carbon dioxide makes up approximately 0.04% of Earth's atmosphere. If you collect a 2.9 L sample from the atmosphere at sea leve
    15·1 answer
  • A free falling object eventually stops on reaching the ground. What happens to its potential energy?
    10·1 answer
  • The law of conservation of energy states that when one from of energy is converted into another ,
    7·1 answer
  • Which of the following will cause water to change to ice!
    6·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!