What Do You Know About Free Fall? Trivia Quiz

Explanation
When the stone is thrown straight up, it experiences a deceleration due to the force of gravity pulling it downward. The acceleration due to gravity is always directed towards the center of the Earth, so when the stone is moving upwards, the acceleration is opposite in direction to its motion. Therefore, the acceleration on the way up is -9.8 m/s2.

Explanation
When the stone reaches its highest point, its velocity is zero because it has stopped moving momentarily. However, its acceleration is not zero because gravity is still acting on the stone, pulling it downward. The stone is undergoing negative acceleration due to gravity, causing it to slow down and eventually reverse direction. Therefore, the correct answer is "its velocity is zero and its acceleration is not zero."

Explanation
When an object is thrown upwards, its initial velocity is positive and it experiences a constant acceleration due to gravity in the opposite direction. As a result, the object slows down until it reaches its highest point and then starts to fall back down. The time it takes to reach the highest point is the same as the time it takes to fall back down to the projection point. Using the equation of motion, we can calculate the time it takes to reach the highest point. Using this time, we can then calculate the height reached using the equation of motion for displacement. In this case, the object reaches a height of 10 m above the projection point.

Explanation
The height of the bridge can be determined using the equation of motion for free fall: h = 1/2 * g * t^2, where h is the height, g is the acceleration due to gravity, and t is the time. Plugging in the given values, we get h = 1/2 * 9.8 m/s^2 * (2.3 s)^2 = 26.285 m. Since the height cannot be measured with such precision, it is rounded to the nearest meter, which is 26 m.

Explanation
The depth of the crater can be determined using the equation of motion for free fall: d = 1/2 * g * t^2, where d is the depth, g is the acceleration due to gravity, and t is the time. Plugging in the given values, we have d = 1/2 * 1.62 m/s^2 * (6.3 s)^2 = 32 m.