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
maks197457 [2]
3 years ago
8

A 49.0 kg wheel, essentially a thin hoop with radius 0.730 m, is rotating at 114 rev/min. It must be brought to a stop in 22.0 s

. (a) How much work must be done to stop it? (b) What is the required average power? Give absolute values for both parts.
Physics
1 answer:
belka [17]3 years ago
4 0

Explanation:

Mass of the wheel, m = 49 kg

Radius of the hoop, r = 0.73 m

Initial angular speed of the wheel, \omega_i=114\ rev/min = 11.93\ rad/s

Final angular speed of the wheel, \omega_f=0

Time, t = 22 s

(a) If I is the moment of inertia of the hoop. It is equal to,

I=mr^2

I=49\times (0.73)^2

I=26.11\ kg-m^2

We know that the work done is equal to change in kinetic energy.

W=\Delta E

W=\dfrac{1}{2}I(\omega_f^2-\omega_i^2)

W=-\dfrac{1}{2}\times 26.11\times (11.93^2)

W = -1858.05 Joules

(b) Let P is the average power. It is given by :

P=\dfrac{W}{t}

P=\dfrac{1858.05\ J}{22\ s}

P =84.45 watts

Hence, this is the required solution.

You might be interested in
A surveyor is using a magnetic compass 6.4 m below a power line in which there is a steady current of 120 A. (a) What is the mag
Mademuasel [1]

Answer:

Explanation:

Magnetic field due to a long current carrying conductor

μ₀ / 4π x 2i / r  ( i = current , r = distance of point from wire )

= 10⁻⁷ x 2 x 120 / 6.4  ( i = 120 A , r = 6.4m )

= 37.5 x 10⁻⁷ T .

= 3. 75 X 10⁻⁶ T .

= 3.75 µT.

b )

The direction of this field will be horizontal hence it will affect magnetic needle.

6 0
4 years ago
Read 2 more answers
g ) (62.44 pts.) Explain why a maximum or a minimum of occurs exactly when an inflection point occurs for
Ivan

Answer:

we approach a maximum or minimum the values ​​of the ordinate are closer and closer and when passing this point the values ​​change their trend

Explanation:

The reason for this process occurs because as we approach a maximum or minimum the values ​​of the ordinate are closer and closer and when passing this point the values ​​change their trend if they were rising, they begin to fall and if they were falling they begin to rise. Therefore the maximum point is a point of inflection of the curve since its trend changes.

Another way of looking at this process is that mathematically the point where there is a maximum or a minimum corresponds to the point where the first derivative is equal to zero, this is the slope of the line is horizontal, so the points before after correspond to values ​​with slope of different sign.

4 0
3 years ago
Angular oscillation of the slotted link is achieved by the crank OA, which rotates clockwise at the steady speed N = 118 rev/min
Leni [432]

Answer:

Angular velocity will be 65.3 rad/s

7 0
4 years ago
Read 2 more answers
When a honeybee flies through the air, it develops a charge of +20 pC . Part A How many electrons did it lose in the process of
Yuri [45]

Answer:

1.3 × 10⁸ e⁻

Explanation:

When a honeybee flies through the air, it develops a charge of +20 pC = + 20 × 10⁻¹² C. This is a consequence of losing electrons (negative charges). The charge of 1 mole of electrons is 96468 C (Faraday's constant). The moles of electrons representing 20 pC are:

20 × 10⁻¹² C × (1 mol e⁻/ 96468 C) = 2.1 × 10⁻¹⁶ mol e⁻

1 mole of electrons has 6.02 × 10²³ electrons (Avogadro's number). The electrons is 2.1 × 10⁻¹⁶ moles of electrons are:

2.1 × 10⁻¹⁶ mol e⁻ × (6.02 × 10²³ e⁻/ 1 mol e⁻) = 1.3 × 10⁸ e⁻

7 0
4 years ago
Can someone help me PLEASE I will mark Brainly and 10+ points
yanalaym [24]

#10 when you added the oil to the water they did not mix together. Instead the oil created a layer on the surface of the water. This is because oil is less dense than water and so it floats

5 0
3 years ago
Read 2 more answers
Other questions:
  • The sun heats Earth mainly through A) fusion. B) radiation. C) conduction. D) convection.
    12·2 answers
  • What kind of map might have diagrams of air pressure?
    11·1 answer
  • A rocket in deep space has an empty mass of 220 kg and exhausts the hot gases of burned fuel at 2500 m/s. What mass of fuel is n
    6·1 answer
  • Becca paddles about from the south bank of a stream to the North Bank. She paddles at a rate of 8 mph the stream is the followin
    14·2 answers
  • A 1200 kg vehicle initially travelling at 50. km/h experiences an air resistance of 5000 N and road friction of 2200 N. The whee
    6·1 answer
  • A turtle ambles leisurely, as turtles tend to do, when it moves from a location with position vector ????1,x=1.33 m and ????1,y=
    10·1 answer
  • Why in example multiplying the length by 2
    12·1 answer
  • A laboratory technician drops a 72.0 g sample of unknown solid material, at a temperature of 80.0°C, into a calorimeter. The cal
    7·1 answer
  • Differentiate the 3 layers of skin. (Epidermis dermis n hypodermis to be exact)
    12·1 answer
  • Which is an SI base unit that makes up part of the unit of energy?
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!