As shown below, an object with a mass of 5 kg is moving at a speed of 10 m/s. Another object with a mass of 10 kg is moving at a speed of 5 m/s.

Which of the objects has higher kinetic energy?

(1 point)
Responses

The 10 kg object has higher kinetic energy.
The 10 kg object has higher kinetic energy.

Both objects have zero kinetic energy.
Both objects have zero kinetic energy.

The 5 kg object has higher kinetic energy.
The 5 kg object has higher kinetic energy.

The objects have equal kinetic energy.
The objects have equal kinetic energy.
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1 answer

To calculate the kinetic energy (KE) of each object, we can use the kinetic energy formula:

\[ KE = \frac{1}{2} mv^2 \]

Where:

  • \( m \) is the mass of the object,
  • \( v \) is the speed of the object.

Now let's calculate the kinetic energy for each object:

  1. For the 5 kg object moving at 10 m/s: \[ KE_1 = \frac{1}{2} (5 , \text{kg}) (10 , \text{m/s})^2 \] \[ KE_1 = \frac{1}{2} (5) (100) \] \[ KE_1 = \frac{1}{2} (500) \] \[ KE_1 = 250 , \text{J} \]

  2. For the 10 kg object moving at 5 m/s: \[ KE_2 = \frac{1}{2} (10 , \text{kg}) (5 , \text{m/s})^2 \] \[ KE_2 = \frac{1}{2} (10) (25) \] \[ KE_2 = \frac{1}{2} (250) \] \[ KE_2 = 125 , \text{J} \]

Now we compare the two kinetic energies:

  • KE of the 5 kg object = 250 J
  • KE of the 10 kg object = 125 J

Therefore, the 5 kg object has a higher kinetic energy.

The correct response is: The 5 kg object has higher kinetic energy.