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Describe the motion of the following objects if they are observed from the
stated frames of reference:
a. a person standing on a platform viewed from a train traveling north
b. a train traveling north viewed by a person standing on a platform
c. a ball dropped by a boy walking at a speed of 1 m/s viewed by the boy
d. a ball dropped by a boy walking 1 m/s as seen by a nearby viewer who
is stationary​

show work !

Answers

  • Réponse publiée par: hannahleigh

    answer: i think c

    explanation:

  • Réponse publiée par: kirbydimaranan

    1. The power in delivering the load is 13,230 Watts.

    2. The power developed from a jumbo jet is 25 Mega Watts or 25x10^{6} Watts.

    Explanation:

    Power is the time rate at which work is done.

    Useful Conversions:

    1 horsepower (hp) = 550 ft.lb/s

    1 hp =746 Watts

    Formula for Power is:

    P=\frac{W}{t}                         equation 1

    P=\frac{W}{t} =\frac{F.s}{t} =Fv      equation 2

    where

    P     is power, unit is in Watts (metric) or horsepower, hp (British system)

    W    is work, unit is in Newton-meter (N.m) or Joules (J)

    v      is velocity, unit is in m/s

    t      is time, unit is in seconds

    Formula for Work is:

    W=Fs

    where

    W     is work done on a body, unit is in N.m or Joules

    F     is force, unit is in Newtons (N)

    s      is the distance, unit is in meters (m)

    Formula for Force is:

    F=mg

    where

    F     is the force, unit is in Newtons (N)

    m     is the mass, unit is in kg

    g      is the acceleration due to gravity equal to 9.8 \frac{m}{s^{2} }

    1. Solving for the power for problem #1 with the following given:

    P=?,   m=1800kg,   s=15m,   t=20s

    a. Solve first for the force, we get:

    F=mg

    F=(1800kg)(15m)

    F= 17640N

    b. Then, substitute the force to solve for work, we get:

    W=Fs

    W=(17640N)(15m)

    W=264600N.m

    c. Now, substitute the answer of work to the formula for power, we get:

    P=\frac{W}{t}

    P=\frac{264,600N.m}{20s}

    P=13,230 Watts

    2. Solving for power in problem #2 with the following given:

    P=?,   v=250m/s,   F=100,000N

    a. Solving the power using equation 2, we get:

    P=\frac{W}{t} =\frac{F.s}{t} =Fv

    P=Fv

    P=(100,000N)(250m/s)

    P=25,000,000 Watts or

    P=25MW or mega Watts

    For more information about Power, just click on the following links:

    * More example about power, work and force

     

    * Relationship between power, work and energy

     

    * Real life application for work, energy and power

     

    #LetsStudy

  • Réponse publiée par: cleik

    Good Day

    Problem:

    a ball thrown straigjt upward. If it takes 4.25 seconds to reach the top of its path, what is its initial speed? ​

    Given Data:

    Vi (initial velocity) = ? unknown

    Vf (final velocity) = 0 m/s (at top)

    t (time)  =  4.25 s

    a (acceleration) = -9.8 m/s² (going up decelerating)

    Solution:

    We can solve the problem using the formula a = (Vf-Vi)/t

    To solve for Vi, we can use - Vi = at Vf

    - Vi = at Vf

    - Vi = -9.8 m/s² × 4.25 s + 0 m/s

    - Vi = - 41.65 m/s + 0 m/s

    ( - Vi = - 41.65 m/s) × -1

      Vi = 41.65 m/s

    Hope it helps=)

    Initial Velocity is 41.65 m/s

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Describe the motion of the following objects if they are observed from the stated frames of referenc...