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
svet-max [94.6K]
3 years ago
13

One simple model for a person running the 100 m dash is to assume the sprinter runs with constant acceleration until reaching to

p speed, then maintains that speed through the finish line. If a sprinter reaches his top speed of
Physics
1 answer:
yaroslaw [1]3 years ago
3 0

Complete Question:

One simple model for a person running the 100 m dash is to assume the sprinter runs with constant acceleration until reaching top speed, then maintains that speed through the finish line. If a sprinter reaches his top speed of 11.5 m/s in 2.24 s, what will be his total time?

Answer:

total time = 6.24 s

Explanation:

Using the equation of motion:

v = u + at

initial speed, u = 0 m/s

v = 11.5 m/s

t = 2.24 s

11.5 = 0 + 2.24a

a = 11.5/2.24

a = 5.13 m/s²

For the total time spent by the sprinter:

s = ut + 0.5at²

100 = 0.5 * 5.13 * t²

t² = 100/2.567

t² = 38.957

t = √38.957

t = 6.24 s

You might be interested in
"175 years" is a measurement of a _____ quantity ?
Aneli [31]
I think the correct answer is b
Hope this help u?
7 0
3 years ago
Find the magnitude of the average induced emf in the coil when the magnet is turned off and the field decreases to 0 T in 2.8 s
Ostrovityanka [42]

Answer:

<em>2.15 mV</em>

<em></em>

Explanation:

The complete question is

You have a coil of wire with 17 turns each of 1.5 cm radius. You place the plane of the coil perpendicular to a 0.50-TB?  field produced by the poles of an electromagnet.

Find the magnitude of the average induced emf in the coil when the magnet is turned off and the field decreases to 0 T in 1.9 s .

Radius of the coil = 1.5 cm = 0.015 m

number of turns = 17

Initial magnetic field B_{1} = 0.50 T

Final magnetic field B_{2} = 0 T

time taken dt = 1.9 s

Area pf the coil = πr^{2} = 3.142 x 0.015^{2} = 7.1 x 10^-4 m^2

magnetic flux = BA

initial flux = B_{1}A = 0.5 x 7.1 x 10^-4 = 3.55 x 10^-4 Wb

Final flux = B_{2}A = 0 x 7.1 x 10^-4 = 0 Wb

change in flux dФ = 3.55 x 10^-4  -  0 = 3.55 x 10^-4 Wb

Induced EMF E = NdФ/dt = (17 x 3.55 x 10^-4)/2.8 = 2.15 x 10^-3 V

==> <em>2.15 mV</em>

7 0
4 years ago
Why must you use temperature to specify how hot or cold something is?
neonofarm [45]

Explanation:

Well to come to think because using the terms hot and cold can be confusing

3 0
3 years ago
Read 2 more answers
A roller coaster starts from rest at the top ofan 18m hill.
KonstantinChe [14]

Answer:

12.65 m/s

Explanation:

When friction is ignored, if the car travels from 18m hill to the bottom of the hill, afterwards it travels up to a 10m hill, then overall it has traveled a distance of 18 - 10  = 8 m vertically.

If the car starts from rest, then its potential energy is converted to kinetic energy:

E_p = E_k

mgh = mv^2/2

where m is the car mass and h is the vertical distance traveled, v is the car velocity at 10m hill

Let g = 10m/s^2. We can cancel m from both sides of the equation:

gh = v^2/2

v^2 = 2gh = 2*10*8 = 160

v^2 = 160

v = \sqrt{160} = 12.65 m/s

7 0
3 years ago
List at least three practices that have resulted from the impact factor. Argue which of these is most problematic and explain wh
Mila [183]
We’ve all noticed that science has been accelerating and a very fast rate resulting in what has been called information overload and more recently filter failure. There are now more researchers add more papers than ever which has led to the importance of bibliometric measures Bibliometric as a Field is a fairly new discipline but it has seen in impressive growth in years due to computation and data storage. Journal metrics can play an important role for editors. There are many different metrics
5 0
3 years ago
Other questions:
  • Please Please Please Can Help Me On This Question!!!!! I Give Thanks!!!!
    5·1 answer
  • Which involves reflection of light waves? A. A full moon shows sunlight bouncing off the moon's surface and traveling toward Ear
    8·2 answers
  • Jon recently drove to visit his parents who live 648 miles away. On his way there his average speed was 14 miles per hour faster
    10·2 answers
  • What is the relationship between an object’s temperature and its heat?
    9·1 answer
  • _______ says the universe began as a point and expanded. A. Evolution B. The Big Bang theory C. Cosmology D. Hubble's law
    6·2 answers
  • An infinitely long line charge of uniform linear charge density λ = -3.00 µC/m lies parallel to the y axis at x = -3.00 m. A poi
    10·1 answer
  • An element’s __________ is its row in the periodic table.
    8·1 answer
  • Which diagram best shows the results of removing heat from the original sample until it freezes?
    8·1 answer
  • The solid shaft with a 20 mm radius is used to transmit the torques applied to the gears. Determine the maximum torsional shear
    6·1 answer
  • 2. a) A student obtained ice at 0°C from a refrigerator and placed it in a beaker on a
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!