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
djverab [1.8K]
3 years ago
13

PLEASE HELP! I don't get it at all! Speed is one thing; distance is another. Where is the arrow you shoot up at 50m/s when it ru

ns out of speed?
Physics
2 answers:
LuckyWell [14K]3 years ago
4 0
I got you b, V(final)^2=V(initial+2acceleration*displacement
So this turns to (0m/s)^2=(50m/s)^2+2(9.8)(d) so just flip it all around to isolate d so you get
-(50m/s)^2/2(9.8) = d so you get roughly 12.7555 meters up
alina1380 [7]3 years ago
3 0
... Gravity makes it go 9.8 m/s slower each second.
    So it runs out of speed in (50/9.8) = 5.1 seconds after the shot.

... At the beginning of the shot, its speed is 50 m/s.
    When it runs out of speed, its speed is zero.
    Its AVERAGE speed during the whole 5.1 seconds is  25 m/s .

... Going straight up for 5.1 seconds, at an average speed of  25 m/s,
     it rises to an altitude of

                               (25 m/s) x (5.1 sec)  =  127.5 meters  .

(You said you have an answer of 125 meters.
Whoever worked out that one probably used 10 m/s²
for the acceleration of gravity, instead of the 9.8 that I used.) 


Of course, once the arrow "runs out of speed", it starts falling,
faster and faster, until it hits the ground.  You could calculate
how long it takes to fall, and how fast it's going when it hits the
ground.  But all of that is for another question.

You might be interested in
A force of 20 N produces an acceleration of 10 m/s² in mass m1 and an acceleration of 5 m/s² in
Scrat [10]

Explanation:

F = 20N m= m1 a=10m/s²

m=m2 a=5m/s²

F = ma

<u>for the first one</u><u>:</u><u> </u>

f=m1 × a

20 = m1 ×10

20=10m1

m1=20/10

m1=2

<u>for</u><u> </u><u>the</u><u> </u><u>second</u><u> </u><u>one</u><u> </u><u>:</u>

f=m2×a

20=m2×5

m2= 20/5

m2= 4

since F=ma

F=(m1+m2) ×a

F =(4+2)×a

F =6×a

F=20(from the question above )

20=6×a

a=20/6

a=3.33

8 0
3 years ago
Read 2 more answers
Use your knowledge of waves to explain why echoes occur. Use your explanation to devise a system to measure distances to objects
german

Explanation:

Echoes occur due to the reflection of sound from any obstacle, but not all the reflected sound waves lead to the phenomenon of echo. For the echo to be heard it actually depends upon the human perception as well, human ears can encounter the difference between the sound wave directly form the source and the reflected sound waves only if there is a minimum time gap of one-tenth of a second. For this time gap in the atmosphere at normal temperature and pressure the obstacle must be at least 7 meters away from the sound source.

3 0
3 years ago
A 0.400-kg object is swung in a circular path and in a vertical plane on a 0.500-m-length string. If the angular speed at the bo
Talja [164]

Answer:

T = 16.72 N

Explanation:

When the object is swung in a circular path, and in a vertical plane, there are two forces external to the object acting on it at any time: the gravity (which is always downward) and the tension in the string (which always points towards the center of the circle).

At the bottom of the circle, the tension is directly upward, so these two forces, are opposite each other, and the difference between them is the centripetal force , which at this point, keeps the object swinging in a circle.

This is the point of the trajectory where T is maximum.

We can apply Newton's 2nd Law, choosing an axis vertical (y-axis) being the upward direction the positive one, as follows:

T- m*g = m*a

The acceleration, at the bottom of the circle, is only normal (as there are no forces in the horizontal direction) , and is equal to the centripetal acceleration, as follows:

ac =  v² / r = ω²*r⇒ T- m*g = m*ω²*r

Replacing by the givens, we can solve for T as follows:

T = m* (ω²*r+g) = 0.4 kg*((8.00)² rad/sec²*0.5m)+9.8 m/s²) = 16.72 N

5 0
3 years ago
Near the surface of the earth, objects in free fall (but not terminal velocity) experience
Mice21 [21]
D. Constant Acceleration
7 0
3 years ago
A mole of red photons of wavelength 725 nm has ________ kj of energy.
yuradex [85]
According to the general rules and basic knowledge of physics, without any doubds I can say that a mole of red photons of wavelength 725 nm has  [D] 165 kj of energy. I converted <span> a wavelength into energy in that way : 
</span>(E)= 6.023 x 10 ^23 x 6.625 x 10 ^ -34 x3 x 10^8/725x10^-9==0.1651 x10 ^ 6 J = 165 Kj.<span>
</span>
7 0
3 years ago
Read 2 more answers
Other questions:
  • From the earth, the moon subtends an angle of approximately 0.5°. If the distance to the moon is approximately 240,000 miles, fi
    11·2 answers
  • 1. If the strength of the magnetic field at B is 3 units, the strength of the magnetic field at A is _____.
    13·1 answer
  • How to solve these two questions ?​
    12·1 answer
  • You have a spring with k = 640 N/m connected to a mass with m = 10 kg. You start the system oscillating and measure the velocity
    12·1 answer
  • Can you help me answer this?
    11·1 answer
  • An object accelerates from rest, with a constant acceleration of 14.5 m / s, what will its velocity be after 92 s?
    10·1 answer
  • The coefficient of kinetic friction between an object and the surface upon which it is sliding is 0.46. The weight of the object
    10·1 answer
  • Use the scenario below for questions 4-7.
    11·1 answer
  • A long thing bar of copper is heated evenly along it's length
    11·1 answer
  • What are the three elements that magnets are made of?
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!