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
aniked [119]
3 years ago
5

In 1998, scientists discovered that the expansion of the universe has been accelerating.

Physics
2 answers:
Lynna [10]3 years ago
8 0
Dang that’s a cool fact bro
klio [65]3 years ago
6 0

Answer:

wow

Explanation:

You might be interested in
A bus traveling at 24 m/s slows down to 12 m/s in 5.0 seconds. What is the acceleration?
Contact [7]

Answer:

a = -2.4 m/s²

Explanation:

Given,

The initial speed of the bus, u = 24 m/s

The final speed of bus, v = 12 m/s

Time taken to reach final speed is, t = 5.0 s

The acceleration of the body is given by the change in velocity by time

                                      a = (v - u) / t

                                         = (12 - 24) / 5

                                         = -2.4 m/s²

The negative sign in the acceleration indicates that the bus is decelerating.

Therefore, the acceleration of the bus is, a = -2.4 m/s²

8 0
2 years ago
A rock is thrown at a window that is located 18.0 m above the ground. The rock is thrown at an angle of 40.0° above horizontal.
Korvikt [17]

Answer:

B) 27.3 m

Explanation:

The rock describes a parabolic path.

The parabolic movement results from the composition of a uniform rectilinear motion (horizontal ) and a uniformly accelerated rectilinear motion of upward or downward motion (vertical ).

The equation of uniform rectilinear motion (horizontal ) for the x axis is :

x =  vx*t   Equation (1)

Where:  

x: horizontal position in meters (m)

t : time (s)

vx: horizontal velocity  in m/s  

The equations of uniformly accelerated rectilinear motion of upward (vertical ) for the y axis  are:

(vfy)² = (v₀y)² - 2g(y- y₀)    Equation (2)

vfy = v₀y -gt    Equation (3)

Where:  

y: vertical position in meters (m)  

y₀ : initial vertical position in meters (m)  

t : time in seconds (s)

v₀y: initial  vertical velocity  in m/s  

vfy: final  vertical velocity  in m/s  

g: acceleration due to gravity in m/s²

Data

v₀ = 30 m/s , at an angle  α=40.0° above the horizontal

v₀x = vx = 30*cos40° = 22.98 m/s

v₀y = 30*sin40° = 19.28 m/s

y₀ = 2m

y =  18.0 m

g = 9.8 m/s²

Calculation of the time (t) it takes for the rock to reach at  18 m above the ground

We replace data in the equation (2)

(vfy)² = (v₀y)² - 2g(y- y₀)    

(vfy)² = (19.28)² - 2(9.8)(18- 2)

(vfy)² = 371.86 - 313.6

(vfy)² = 58.26

v_{f} = \sqrt{58.26}

vfy = 7.63 m/s

We replace vfy = 7.63 m/s in the equation (2)

vfy = v₀y - gt

7.63 = 19.28 - (9.8)(t)

(9.8)(t) = 11.65

t = 11.65 / (9.8)

t = 1.19 s

Horizontal distance from where the rock was thrown to the window

We replace t = 1.19 s , in the equation (1)

x =  vx*t  

x = (22.98)* ( 1.19 )

x = 27.3 m

3 0
3 years ago
Which of the following is not a reason fluorescent lamps are advantageous over incandescent lamps?
cricket20 [7]

Answer;

B. Fluorescent lamps operate at a higher temperature than incandescent lamps.

Explanation;

-A fluorescent lamp, is a type of electric light (lamp) that uses ultraviolet emitted by mercury vapor to excite a phosphor, which emits visible light.

-A fluorescent lamp produces less heat, thus, it is much more efficient. A fluorescent bulb can produce between 50 and 100 lumens per watt. This makes fluorescent bulbs four to six times more efficient than incandescent bulbs.

-Fluorescent lamps operate best around room temperature. At much lower or higher temperatures, efficacy decreases.

4 0
2 years ago
Read 2 more answers
Scientific work is currently underway to determine whether weak oscillating magnetic fields can affect human health. For example
iragen [17]

Given Information:

Magnetic field = B = 1×10⁻³ T

Frequency = f = 72.5 Hz

Diameter of cell = d = 7.60 µm = 7.60×10⁻⁶ m

Required Information:

Maximum Emf = ?

Answer:

Maximum Emf = 20.66×10⁻¹² volts

Explanation:

The maximum emf generated around the perimeter of a cell in a field is given by

Emf = BAωcos(ωt)

Where A is the area, B is the magnetic field and ω is frequency in rad/sec

For maximum emf cos(ωt) = 1

Emf = BAω

Area is given by

A = πr²

A = π(d/2)²

A = π(7.60×10⁻⁶/2)²

A = 45.36×10⁻¹² m²

We know that,

ω = 2πf

ω = 2π(72.5)

ω = 455.53 rad/sec

Finally, the emf is,

Emf = BAω

Emf = 1×10⁻³*45.36×10⁻¹²*455.53

Emf = 20.66×10⁻¹² volts

Therefore, the maximum emf generated around the perimeter of the cell is 20.66×10⁻¹² volts

8 0
3 years ago
Which statement is TRUE? A) In a series circuit, the resistors do not share the current. B) In a series circuit, as light bulbs
3241004551 [841]

The answer is B, actually did the research

7 0
3 years ago
Read 2 more answers
Other questions:
  • Please someone help me lol
    9·1 answer
  • Why do earthquakes and volcanoes occur along continent and ocean boundaries?
    11·2 answers
  • 1.) Starting from rest, a car accelerates at 6.52 m/s^2 for 3.80 s. Determine the distance traveled by the car during this time.
    15·1 answer
  • Hat do the ancient civilizations of China, Egypt, and Greece have in common with regard to sports?
    5·1 answer
  • Now, consider whether the following statements are true or false:_____________________________________.
    14·1 answer
  • If you had a 30 pound barbell at home and you wanted to compare your muscular endurance to your younger brother's which method w
    11·1 answer
  • Select the correct equations that show that a freely falling rock drops a distance of 80 m when it falls from rest for 4 s .
    15·1 answer
  • Which of the following is the most appropriate definition of organic compound?
    9·2 answers
  • A girl stand 5m away from a large plane mirror.How far must she walk ti be 2m away from her image?​
    11·1 answer
  • It has been suggested that rotating cylinders about 14.5 mi long and 4.78 mi in diameter be placed in space and used as colonies
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!