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
prohojiy [21]
3 years ago
14

A mass of 5kg starts from rest and pulls down vertically on a string wound around a disk-shaped, massive pulley. The mass of the

disk is 5kg and its radius is 2 m. What is the linear speed, in m/s, after the mass drops by 0.3 m?
a. 0.5
b. 1.5
c. 2
d. 3
e.5
Physics
1 answer:
Paha777 [63]3 years ago
8 0

Answer:

c. V = 2 m/s

Explanation:

Using the conservation of energy:

E_i =E_f

so:

Mgh = \frac{1}{2}IW^2 +\frac{1}{2}MV^2

where M is the mass, g the gravity, h the altitude, I the moment of inertia of the pulley, W the angular velocity of the pulley and V the velocity of the mass.

Also we know that:

V = WR

Where R is the radius of the disk, so:

W = V/R

Also, the moment of inertia of the disk is equal to:

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

I = \frac{1}{2}(5kg)(2m)^2

I = 10 kg*m^2

so, we can write the initial equation as:

Mgh = \frac{1}{2}IV^2/R^2 +\frac{1}{2}MV^2

Replacing the data:

(5kg)(9.8)(0.3m) = \frac{1}{2}(10)V^2/(2)^2 +\frac{1}{2}(5kg)V^2

solving for V:

(5kg)(9.8)(0.3m) = V^2(\frac{1}{2}(10)1/4 +\frac{1}{2}(5kg))

V = 2 m/s

You might be interested in
In what regions of the electromagnetic spectrum is the atmosphere transparent enough to allow observations from the ground?
MissTica

Answer:

Visible Light and Radio waves

Explanation:

The earth's atmosphere is transparent to a few windows in the electromagnetic spectrum. it is completely transparent to allow observation from the ground in visible light rang 380 to 740 nano meters. Also in the range of radio wave as communication are done from space to ground in the form of radio waves.

it is Partially transparent to Microwave and infrared range.

3 0
3 years ago
Which condition is necessary for total internal reflection? A. The refracted ray should lie along the boundary of the two media.
g100num [7]

There are two conditions necessary for total internal reflection, which is when light hits the boundary between two mediums and reflects back into its original medium:

Light is about to pass from a more optically dense medium (slower) to a less optically dense medium (faster).

The angle of incidence is greater than the defined critical angle for the two mediums, which is given by:

θ = sin⁻¹(n_{fast}/n_{slow})

Where θ = critical angle, n_{fast} = refractive index of faster medium, n_{slow} = refractive index of slower medium.

Choice C gives one of the above necessary conditions.

6 0
3 years ago
A pelican hunts fish in the water. As the pelican flies above the water’s surface, why must it aim for the fish in a slightly di
GarryVolchara [31]

Answer

A

Explanation

The light the fish absorbs is sunlight, the light reflecting is UV

5 0
3 years ago
Compare and contrast speed and velocity.​
vlabodo [156]

Speed is the time rate of an object moving from one place to another, while velocity is the rate and direction of the object's movement. They are very similar but they don't mean the same thing.

8 0
2 years ago
What increases your ability to see at night
PtichkaEL [24]
The answer would be increased number <span />of rod cells.Hope this helps :)


8 0
3 years ago
Other questions:
  • A flask that weighs 345.8 g is filled with 225 mL of carbon tetrachloride. The weight of the flask and carbon tetrachloride is f
    10·1 answer
  • A 425 g block is released from rest at height h0 above a vertical spring with spring constant k = 460 N/m and negligible mass. T
    11·2 answers
  • If you cannot get a chair to move across the floor, it is because ___ friction opposes your push.
    8·1 answer
  • HELP PLEASE!!!!! (Apex)
    11·2 answers
  • A scientist observes debris added to a landform from a melting glacier. This is evidence for which type of natural process?
    13·2 answers
  • A street light is at the top of a 13.0 ft. tall pole. A man 6.3 ft tall walks away from the pole with a speed of 3.5 feet/sec al
    13·1 answer
  • When electromagnetic fields interact with charged particles,
    12·2 answers
  • (a) (i) Find the gradient of f. (ii) Determine the direction in which f decreases most rapidly at the point (1, −1). At what rat
    13·1 answer
  • Which statement correctly summarizes Wegener’s theory of continental drift?
    6·2 answers
  • What are the factors of works?
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!