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a dog and a squirrel run down a hill at the same speed. the dog has a mass of 6 kilograms. the squirrel has a mass of 1 kilogram. which animal has more kinetic energy as it runs down the hill

User Pjz
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Answer:

The dog will have a higher kinetic energy.

Step-by-step explanation:

Kinetic energy (K.E) is simply defined as the energy an object possess in motion.

Mathematically, it expreessed as:

K.E = ½mv²

Where:

K.E is the kinetic energy.

m is the mass of the object.

v is the velocity of the object.

From the above equation, we can say that:

Kinetic energy is directly proportional to the mass of the object and also to the square of the velocity of the object.

Thus, object with higher mass will have a greater kinetic energy than object with lesser mass even if they have the same velocity.

From the question given above, the dog has a mass of 6 kg while the squirrel has a mass of 1 kg.

Since they have the same speed, the dog will have a higher kinetic energy because it has a higher mass than the squirrel.

Thus, we can further justify this concept as follow:

Let the speed of both animals be 2 m/s

Thus their kinetic energy can be obtained as follow:

For Dog:

Mass (m) = 6 kg

Velocity (v) = 2 m/s

Kinetic energy (K.E) =.?

K.E = ½mv²

K.E = ½ × 6 × (2)²

K.E = 3 × 4

K.E = 12J

Therefore, the kinetic energy of the dog is 12 J

For Squirrel:

Mass (m) = 1 kg

Velocity (v) = 2 m/s

Kinetic energy (K.E) =.?

K.E = ½mv²

K.E = ½ × 1 × (2)²

K.E = ½ × 1 × 4

K.E = 1 × 2

K.E = 2 J

Therefore, the kinetic energy of the squirrel is 2 J.

Summary:

Kinetic energy of dog = 12 J

Kinetic energy of squirrel = 2 J

From the above, we can see clearly that though both animals have the same speed, the dog has a higher kinetic energy than the squirrel because it has a higher mass.

User Waynn Lue
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