How Long Will It Take for the Rescue Ship to Reach You?

AI Thread Summary
To determine how long it will take for a rescue ship to reach a person in a lifeboat, one must first calculate the distance to the ship when its flag becomes visible. Given that the ship is 12m tall and the observer's eye level is 1m above the water, the distance to the horizon can be calculated using the Earth's radius. The ship travels at a constant speed of 5m/s, allowing for a straightforward calculation of time based on the distance once the flag is visible. Understanding concepts like tangential velocity and angular motion can aid in grasping the dynamics involved. Ultimately, the answer should be expressed in the most common measure of time, such as seconds or hours.
bukky
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You are sitting in a life boat at rest on a calm se, with your eye 1m above the water. A rescue ship is moving directly toward you at a constant speed of 5m/s. If the tallest point on the ship is 12m above the water, how long will the ship take to reach you from the moment when you can first see its flag above the horizon. The Earth's radius is at sea level 6.38x10^3km. Express anwer in the most common measure of time( ie use days, weeks, hours, second)
Thank you
 
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Hi, bukky. Welcome to PF. Please note the sticky just above this thread that says "Don't Post Your Homework Questions Here". There is a section for this.
 
bukky said:
You are sitting in a life boat at rest on a calm se, with your eye 1m above the water. A rescue ship is moving directly toward you at a constant speed of 5m/s. If the tallest point on the ship is 12m above the water, how long will the ship take to reach you from the moment when you can first see its flag above the horizon. The Earth's radius is at sea level 6.38x10^3km. Express anwer in the most common measure of time( ie use days, weeks, hours, second)
Thank you

Think of a point, traveling around some center of mass with a tangential velocity. You may want to research your mathematical definitions of tangential velocity and angular velocity (and tangential acceleration and centripedla acceleration; they're all important equations of motion that depend on speed and velocity like any other equation of motion, but a special feature of angular motion is that some of it's components are a function of the radius of any object with angular motion.
 
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