An object is thrown horizontally from the top of a tower 80 m high. How long wil
Practice Questions
Q1
An object is thrown horizontally from the top of a tower 80 m high. How long will it take to hit the ground?
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Questions & Step-by-Step Solutions
An object is thrown horizontally from the top of a tower 80 m high. How long will it take to hit the ground?
Step 1: Identify the height of the tower, which is 80 meters.
Step 2: Understand that the object is thrown horizontally, so we only need to consider the vertical motion to find out how long it takes to hit the ground.
Step 3: Use the formula for the distance fallen under gravity: h = (1/2)gt², where h is the height (80 m), g is the acceleration due to gravity (approximately 9.8 m/s²), and t is the time in seconds.
Step 4: Substitute the known values into the formula: 80 = (1/2) * 9.8 * t².
Step 5: Simplify the equation: 80 = 4.9 * t².
Step 6: To isolate t², divide both sides by 4.9: t² = 80 / 4.9.
Step 7: Calculate the right side: t² ≈ 16.33.
Step 8: Take the square root of both sides to find t: t ≈ √16.33.
Step 9: Calculate the square root: t ≈ 4 seconds.
Projectile Motion – The question tests understanding of the motion of an object under the influence of gravity, specifically the time it takes for an object to fall a certain height.
Kinematic Equations – The use of the kinematic equation h = (1/2)gt² to calculate the time of free fall is a key concept being tested.