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 objects have equal kinetic energy. The objects have equal kinetic energy. 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.

Question

GPT-4o mini · Answer

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

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

where \( m \) is the mass and \( v \) is the velocity of the object.

For the 5 kg object moving at 10 m/s:

\[ KE_1 = \frac{1}{2} \times 5 , \text{kg} \times (10 , \text{m/s})^2 = \frac{1}{2} \times 5 \times 100 = 250 , \text{J} \]

For the 10 kg object moving at 5 m/s:

\[ KE_2 = \frac{1}{2} \times 10 , \text{kg} \times (5 , \text{m/s})^2 = \frac{1}{2} \times 10 \times 25 = 125 , \text{J} \]

Now, comparing the two kinetic energies:

The 5 kg object has a kinetic energy of 250 J.
The 10 kg object has a kinetic energy of 125 J.

Therefore, the 5 kg object has higher kinetic energy.

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

Answer

Which statement best describes the relationship between a baseball’s potential and kinetic energy after it is thrown? (assume the ball travels in a straight line)(1 point) Responses Potential energy decreases as kinetic energy increases. Potential energy decreases as kinetic energy increases. Potential and kinetic energy both decrease. Potential and kinetic energy both decrease. Potential energy does not change, and kinetic energy decreases. Potential energy does not change, and kinetic energy decreases. Potential energy increases, and kinetic energy does not change.

GPT-4o mini · Answer

When a baseball is thrown, it starts from a position where it has certain potential energy (due to its height relative to the ground) and gains kinetic energy as it is thrown and starts moving.

As the baseball is thrown:

The potential energy (PE) may change depending on the height. If the baseball is thrown from a height and then moves in a straight line, the potential energy will decrease as it descends, but if we assume the height stays mostly constant (like when thrown horizontally), potential energy mainly remains constant.
The kinetic energy (KE) will increase significantly as the baseball is accelerated from rest to the speed it has when thrown.

Since in most cases of throwing a baseball, its height does not change significantly from the throw until it comes down, the primary observation is that as the ball is thrown, potential energy may decrease slightly, and the kinetic energy increases.

Thus, the best description of this relationship would be:

Potential energy decreases as kinetic energy increases.