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answers:
MyRank say: Given,
Kinetic Energy (K.E) = 45,000 Joules
Mass (m) = 28,000 kg
Velocity (V) =?
We know that:-
Kinetic Energy (K.E) = 1/2 mv2
45,000 = 1/2*28,000*v2
45,000 = 14,000*v2
45,000 / 14,000 = v2
→ v2 = 45/14
→ speed (v) = 1.79m/sec
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Fazaldin A say: kinetic energy = mv^2/2 = 45,000 J. and mass, m = 28,000 kg,
So,
v^2 = 2*45000/28000 = 45/14,
Hence,
Velocity, v = sqrt(45/28) = 1,793 m/sec. <-------------------------------/
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Philomel say: A little less than 2 Meters / sec.
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say: Twice the speed of light(give or take) It is just a quick mental approximation.
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Ricki say: What's the formula for KE? Hint, look in your textbook or use google
Substitute and solve.
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oubaas say: 2Ek = m*V^2
V = √2*45.000/28.000 = √90/28 = 1,793 m/sec
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donpat say: You have :
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KE = ( m ) ( v )^2 ( 1/2 )
( v )^2 = ( 2 ) ( KE ) / ( m )
v = [ ( 2 ) ( KE ) / ( m ) ]^1/2
v = [ ( 2 ) ( 45000 J ) ( 1.0 N-m /J ) / ( 28000 kg ) ]^1/2
v = [ 3.214 m^2/s^2 ]^1/2 = 1.793 m/s <--------------------
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Argent say: Ek = ½mv², so v = √(2Ek/m) = √(2(45 000 J)/(28 000 kg)) = 1.8 m/s.
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