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
Andreyy89
2 years ago
10

A sprinter starts from rest and reaches a speed of 15 m/s in 4.25 s. Find his acceleration

Physics
1 answer:
kakasveta [241]2 years ago
5 0

Answer:

a=3.53 m/s^2

Explanation:

Vo=0 m/s (because he is not moving at the start)

V1=15 m/s

t= 4.25 s

a = (V1-Vo) / t = 15/4.25 = 3.53 m/s^2

You might be interested in
What happens to most of the light waves that strike a clear pane of glass
Marysya12 [62]
It’s C


Because C is a reflection which reflects something such as mirror

Hope this helps! •~•
3 0
3 years ago
Read 2 more answers
How much heat is required to convert solid ice with a mass of 985 g and at a temperature of -29.5 °c to liquid water at a temper
liberstina [14]

Consider, please, this solution:

The final heat is:

Q=Q₁+Q₂+Q₃≈726.116 kJ

All the details are in the attachment.

6 0
3 years ago
An elevator is moving is an upwards
Minchanka [31]

Answer:

The elevator's free-body diagram has three forces, the force of gravity, a downward normal force from you, and an upward force from the tension in the cable holding the elevator. The combined system of you + elevator has two forces, a combined force of gravity and the tension in the cable.

Explanation:

6 0
3 years ago
Un the way to the moon, the Apollo astro-
kherson [118]

Answer:

Distance =  345719139.4[m]; acceleration = 3.33*10^{19} [m/s^2]

Explanation:

We can solve this problem by using Newton's universal gravitation law.

In the attached image we can find a schematic of the locations of the Earth and the moon and that the sum of the distances re plus rm will be equal to the distance given as initial data in the problem rt = 3.84 × 108 m

r_{e} = distance earth to the astronaut [m].\\r_{m} = distance moon to the astronaut [m]\\r_{t} = total distance = 3.84*10^8[m]

Now the key to solving this problem is to establish a point of equalisation of both forces, i.e. the point where the Earth pulls the astronaut with the same force as the moon pulls the astronaut.

Mathematically this equals:

F_{e} = F_{m}\\F_{e} =G*\frac{m_{e} *m_{a}}{r_{e}^{2}  } \\

F_{m} =G*\frac{m_{m}*m_{a}  }{r_{m} ^{2} } \\where:\\G = gravity constant = 6.67*10^{-11}[\frac{N*m^{2} }{kg^{2} } ] \\m_{e}= earth's mass = 5.98*10^{24}[kg]\\ m_{a}= astronaut mass = 100[kg]\\m_{m}= moon's mass = 7.36*10^{22}[kg]

When we match these equations the masses cancel out as the universal gravitational constant

G*\frac{m_{e} *m_{a} }{r_{e}^{2}  } = G*\frac{m_{m} *m_{a} }{r_{m}^{2}  }\\\frac{m_{e} }{r_{e}^{2}  } = \frac{m_{m} }{r_{m}^{2}  }

To solve this equation we have to replace the first equation of related with the distances.

\frac{m_{e} }{r_{e}^{2}  } = \frac{m_{m} }{r_{m}^{2} } \\\frac{5.98*10^{24} }{(3.84*10^{8}-r_{m}  )^{2}  } = \frac{7.36*10^{22}  }{r_{m}^{2} }\\81.25*r_{m}^{2}=r_{m}^{2}-768*10^{6}* r_{m}+1.47*10^{17}  \\80.25*r_{m}^{2}+768*10^{6}* r_{m}-1.47*10^{17} =0

Now, we have a second-degree equation, the only way to solve it is by using the formula of the quadratic equation.

r_{m1,2}=\frac{-b+- \sqrt{b^{2}-4*a*c }  }{2*a}\\  where:\\a=80.25\\b=768*10^{6} \\c = -1.47*10^{17} \\replacing:\\r_{m1,2}=\frac{-768*10^{6}+- \sqrt{(768*10^{6})^{2}-4*80.25*(-1.47*10^{17}) }  }{2*80.25}\\\\r_{m1}= 38280860.6[m] \\r_{m2}=-2.97*10^{17} [m]

We work with positive value

rm = 38280860.6[m] = 38280.86[km]

<u>Second part</u>

<u />

The distance between the Earth and this point is calculated as follows:

re = 3.84 108 - 38280860.6 = 345719139.4[m]

Now the acceleration can be found as follows:

a = G*\frac{m_{e} }{r_{e} ^{2} } \\a = 6.67*10^{11} *\frac{5.98*10^{24} }{(345.72*10^{6})^{2}  } \\a=3.33*10^{19} [m/s^2]

6 0
3 years ago
A non-_____ rock has interlocking grains with no specific pattern.
Kazeer [188]
A non <span>foliated </span>rock has interlocking grains with no specific pattern.
3 0
3 years ago
Read 2 more answers
Other questions:
  • A current carrying wire is oriented along the y axis It passes through a region 0.45 m long in which there is a magnetic field o
    7·1 answer
  • After a 50-kg person steps from a boat onto the shore, the boat moves away with a speed of 0.70 m/s with respect to the shore. I
    13·2 answers
  • A spacecraft left Earth to collect soil samples from Mars. Which statement is true about the strength of Earth’s gravity on the
    12·1 answer
  • If a carbon atom has 7 neutrons and 6<br> protons, what is its mass number?
    5·1 answer
  • Nerve signals in the body occur when a small voltage, called an action potential, is applied across the membrane of a cell. When
    10·2 answers
  • Decide if each description below is an example of a change caused by energy. From the drop-down menu, choose "IS" if it is an ex
    7·1 answer
  • 6. Find the magnetic field strength at the centre of a solenoid with
    6·1 answer
  • A satellite is orbiting the earth. If a payload of material is added until it doubles the satellite's mass, the earth's pull of
    8·2 answers
  • An object of mass 100kg is moving with a velocity of 5m/s. Calculate the kinetic energy of that object
    13·2 answers
  • Question 14
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!