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A student drops a ball from a height of 60 meters. The table below shows the ball’s speed and height as time passes.



At what point in time does the ball have the highest kinetic energy?

(1 point)
Responses

At the start (0 seconds)
At the start (0 seconds)

After 0.5 seconds
After 0.5 seconds

After 2 seconds
After 2 seconds

After 2.5 seconds
After 2.5 seconds
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3 answers

To determine at what point in time the ball has the highest kinetic energy, we need to consider the relationship between height, speed, and kinetic energy. Kinetic energy (KE) is given by the equation:

\[ KE = \frac{1}{2} m v^2 \]

where \(m\) is the mass of the ball and \(v\) is its velocity (speed).

As the ball falls, its height decreases while its speed increases due to the acceleration from gravity. The kinetic energy increases as speed increases.

The ball will have the highest kinetic energy just before it hits the ground, as this is when its speed will be at its maximum. Without any specific speed values or height table provided, we can draw the conclusion that:

  • At the start (0 seconds), the ball hasn't started falling, so its speed is 0, meaning its kinetic energy is also 0.
  • As time passes and the ball falls, its speed increases and so does its kinetic energy.
  • Therefore, the highest kinetic energy will occur just before the ball hits the ground.

Since the provided options are after specific intervals of time, it is reasonable to conclude that the ball will have the highest kinetic energy after 2.5 seconds (if that is when it impacts).

So the best answer from the choices given would be:

After 2.5 seconds

is this correct

Let's clarify the situation given the context of a ball dropped from a height of 60 meters. When analyzing the kinetic energy of the ball as it falls, it will indeed have its highest kinetic energy just before it hits the ground because that's when it achieves its maximum velocity.

Here's a breakdown based on typical free fall physics:

  1. At the start (0 seconds): The ball is stationary, so its speed is 0 m/s, and its kinetic energy is also 0.
  2. After 0.5 seconds: The ball has fallen a short distance and its speed has increased, thus it has some kinetic energy.
  3. After 2 seconds: The ball has fallen further and its speed is likely higher, resulting in increased kinetic energy.
  4. After 2.5 seconds: If the ball is still falling, it will have a higher speed than at 0.5 seconds and 2 seconds, leading to even greater kinetic energy.

Assuming the ball has not yet hit the ground at these time intervals, the ball will have continuously increasing speed and thus increasing kinetic energy throughout its fall.

If 2.5 seconds is just before it hits the ground (which is likely since it takes around 3.5 seconds to fall 60 meters in free fall without air resistance), then the correct answer would indeed be:

After 2.5 seconds.

If the ball has reached the ground at 2.5 seconds, then if that’s the end of the measured time slots, the maximum kinetic energy would be immediately before that, which would be at 2 seconds as well.

To summarize, if the question is strictly about the intervals given and if 2.5 seconds is when the ball strikes the ground, then:

  • The ball has the highest kinetic energy after 2 seconds (right before 2.5 seconds) as it would be just before hitting the ground.

Please verify any specific intervals from your data, as my assumptions depend on standard free-fall timing.