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A puppy weighing 3 kilograms races through the dog park. if she slows from a speed of 2 meters/second to 1 meter/second, what will happen to her kinetic energy? use the kinetic energy equation.

a.her kinetic energy decreases to 1.5 j
b.her kinetic energy increases to 1.5 j
c.her kinetic energy remains unchanged
d.her kinetic energy decreases to 1 j.

2 Answers

2 votes
Your answer is A. If velocity decreases, your kinetic energy would also decrease.
User Trisma
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5 votes

Answer:The correct answer is option (a).

Step-by-step explanation:

Mass of the puppy,m = 3 kg

Kinetic energy of the puppy when it was running with speed of 2 m/s:


K.E=(1)/(2)mv^2=(1)/(2)* 3kg* (2 m/s)^2=6 Joules

Kinetic energy of the puppy when it was running with speed of 1 m/s:


K.E'=(1)/(2)mv^2=(1)/(2)* 3kg* (1 m/s)^2=1.5 Joules

When the puppy was running at the speed f 1 m/s her kinetic energy reduced to 1.5 Joules.

Hence, correct answer is option (a).

User Moni
by
7.7k points
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