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The Kentucky Derby is one of the most exciting horse races run every year. In 1973, the horse Secretariat set a record that still stands. This 500-kg horse ran the 2000-m track in 120 s. What was Secretariat's average kinetic energy? (1 kJ = 1000 J)

User Squishy
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2 Answers

4 votes

Answer:C 69.0kJ

Step-by-step explanation:

User Lurline
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2 votes

Answer:

69.44kJ

Step-by-step explanation:

Kinetic energy is expressed as;

KE = 1/2mv^2

m is the mass = 500kg

v is the velocity

Get the velocity;

v = displacement/time

velocity = 2000/120

velcoity = 16.7m/s

Gt the kinetic energy

KE = 1/2 * 500 * 16.7²

KE = 250*277.78

KE = 69,444.4Joules

Since 1000J = 1kJ

69,444.4Joules = 69,444.4/1000

69,444.4Joules = 69.44kJ

Hence the Secretariat's average kinetic energy is 69.44kJ

User Stephen Vernyi
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5.4k points