Calculating Distance, Velocity and Gravity

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To determine how far above the bull's-eye an archer must aim, the time for the arrow to reach the target is calculated as 0.442 seconds using the formula t = d/v. The drop due to gravity over this time is found using d = 1/2 * g * t^2, resulting in a distance of 0.975 meters. For the beach ball, the time it takes to hit the water is calculated as 0.562 seconds, leading to a pier height of 0.264 meters above the water using the same gravitational equation. Both scenarios effectively demonstrate the application of motion equations to account for gravity's effect on projectile motion. Understanding these calculations is essential for accurate aim and height assessments in similar situations.
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An archer stands 42.0 m from the target. If the arrow is shot horizontally with a velocity of 95.0 m/s, how far above the bull's-eye must he aim to compensate for gravity pulling his arrow downward?

A beach ball, moving with a speed of +1.30 m/s rolls off a pier and hits the water 0.73 m from the end of the pier. How high above the water is the pier?

I need some help with these.
 
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To calculate the distance, velocity, and gravity involved in these situations, we can use the equations of motion. For the archer, we can use the equation d = v*t, where d is the distance, v is the velocity, and t is the time. In this case, we are given the distance (42.0 m) and velocity (95.0 m/s), so we can solve for the time it takes for the arrow to reach the target. The equation becomes t = d/v, so t = 42.0 m / 95.0 m/s = 0.442 seconds.

Now, we can use the equation d = 1/2 * g * t^2, where g is the acceleration due to gravity (9.8 m/s^2) and t is the time. We know the time (0.442 seconds) and we want to find the distance above the bull's-eye, so we rearrange the equation to solve for d, giving us d = 1/2 * g * t^2 = 1/2 * 9.8 m/s^2 * (0.442 s)^2 = 0.975 m. This is the distance the arrow will drop due to gravity, so the archer should aim 0.975 m above the bull's-eye to compensate for this drop.

For the beach ball scenario, we can use the same equations. We are given the velocity (1.30 m/s) and the distance traveled (0.73 m), so we can solve for the time using the equation t = d/v. This gives us t = 0.73 m / 1.30 m/s = 0.562 seconds.

Next, we can use the equation d = 1/2 * g * t^2 to find the height of the pier. We know the time (0.562 seconds) and we want to find the height, so we rearrange the equation to solve for h, giving us h = d / (1/2 * g * t^2) = 0.73 m / (1/2 * 9.8 m/s^2 * (0.562 s)^2) = 0.73 m / 2.76 = 0.264 m. This is the height of the pier above the water.

In summary, by using the equations of motion, we can calculate the distance
 
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