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
gulaghasi [49]
3 years ago
12

Alex is standing still and throws a football with a speed of 10 m/s to his friend, who is also standing still. The two friends a

re standing 5 meters apart. Which describes how each person observes the speed of the football?
Physics
2 answers:
Phantasy [73]3 years ago
7 0

The question is incomplete. It comes with a set of answer choices.


These are the answer choices:


Alex observes it as 10 m/s, and his friend observes it as less than 10 m/s.


Alex observes it as less than 10 m/s, and his friend observes it as 10 m/s.


Both Alex and his friend observe it as 10 m/s.


Both Alex and his friend observe it as less than 10 m/s.



Answer: Both Alex and his friend observe it as 10 m/s.


Justification:


1) The speed is relative to the frame of reference.


2) It is said that the both Alex and his friend are standing still.


3) Then, the speed they both see is the same, 10 m/s, respect the Earth (where they are standing still).


Of course, Alex is watching the ball moving away and his friend is seing it approaching, but it is not relevant for the question, as it deals with the speed which is only about magnitude, not direction.

Readme [11.4K]3 years ago
6 0

Answer:

c on edge

Explanation:

You might be interested in
Consider a disk of radius 2.6 cm with a uni- formly distributed charge of +6.7.1C. Compute the magnitude of the electric field a
MrRissso [65]

Answer:

E=15.3*10¹³ N/C  : approximate

Explanation:

We use the following formula to calculate the electric field due to a disk with uniform surface charge at a point P that is along the central perpendicular axis of the disk and at a distance x from the center of the disk:

E= 2*π*k*σ*F  Fórmula ( 1 )

F= 1-\frac{x}{\sqrt{R^{2}+x^{2}  } }

E: Electric field at point P (N/C)

σ: surface charge density (C/m²)

R: disk radio (m)

x :distance from the center of the disk to the point P located on the axis of the disk (m)

K: Coulomb constant ( N*m²/C)

Equivalences

1cm = 10⁻²m

1mm = 10⁻³m

Data

R =2.6 cm= 2.6*10⁻²m = 0.026m

x=3.7 mm = 3.7* 10⁻³m = 0,0037 m

Q=+6.71C.

k= 8.98774 * 10⁹ N* m²/C

Calculation of surface charge density (σ )

σ= Q/A

Q:  uniformly distributed charge (C)

A: disk area (m²) = π*R²

σ= +6.71C/π*(2.6*10⁻²)²m² = 3159.56C/m²

Calculation of the electric field at point P

We apply formula (1) and replace data

E= 2*π*3159.56*8.98774*10⁹ *F

F= 1-\frac{x}{\sqrt{R^{2}+x^{2}  } }

E=15.3*10¹³ N/C  : approximate

3 0
2 years ago
The average weather pattern of a region over a long period of time is known as
Pepsi [2]
B-Climate is the answer.
3 0
3 years ago
While traveling, John let destination A at 9 am. Driving until 7 pm, he travelled a total of 500 miles. The next day, John left
beks73 [17]

18 hours 770

770/18 average speed.

5 0
3 years ago
Read 2 more answers
If you suspect your culture of bacteria has 25 x 107 cells per mL, what would you want the final dilution to be in order to end
Delicious77 [7]

Answer:

dilution = 2.5*10^6

Explanation:

Given:

- Number of colonies N = 100 cfu

- The Volume of cells = 25*10^7 cells / ml

Find:

the final dilution

Solution:

- The expression relating the the colonies forming unit with cells//volume is given as:

                                       Bacteria/ml = cfu*dilution

                                       dilution = Volumetric cells/ cfu

                                       dilution = 25*10^7 / 100

                                       dilution = 2.5*10^6

4 0
2 years ago
I'm sorry this question is deleted
Colt1911 [192]

Answer:

lol

you are so funny.....

8 0
2 years ago
Other questions:
  • Slow moving vehicles that travel at a speed less than ___ mph will have an orange reflective triangle with red around the edges
    7·1 answer
  • You have a meter stick marked to the nearest millimeter. Which of these measurements is written with the correct amount of preci
    5·2 answers
  • If Earth were twice as far from the sun, the force of gravity attracting the Earth to the Sun would be
    14·1 answer
  • Sir William Herschel counted the number of stars in different directions, and getting similar numbers in each direction along th
    12·1 answer
  • A super ball is dropped from a height of 100 feet. Each time it bounces, it rebounds half the distance it falls. How many feet w
    15·1 answer
  • Harrison wanted to find out what soil works best for growing roses. He grew them in potting soil, clay, sand, and soil he found
    9·1 answer
  • What is the purpose of a free body diagram
    5·2 answers
  • The answer and how to do it
    14·1 answer
  • A scientist proposed a hypothesis that burning coal at higher altitudes would release less pollution. The data the scientist col
    14·1 answer
  • Consider again the objects you ranked by distance. Suppose each object emitted a burst of light right now. Rank the objects from
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!