An object is dropped from a height of 20 m. How long will it take to reach the g
Practice Questions
Q1
An object is dropped from a height of 20 m. How long will it take to reach the ground? (Take g = 10 m/s²)
2 s
4 s
3 s
5 s
Questions & Step-by-Step Solutions
An object is dropped from a height of 20 m. How long will it take to reach the ground? (Take g = 10 m/s²)
Step 1: Understand the problem. We need to find out how long it takes for an object to fall from a height of 20 meters.
Step 2: Identify the formula we will use. The formula for the distance fallen under gravity is h = (1/2)gt², where h is the height, g is the acceleration due to gravity, and t is the time in seconds.
Step 3: Plug in the values into the formula. We know h = 20 m and g = 10 m/s². So, we write: 20 = (1/2)(10)t².
Step 4: Simplify the equation. First, calculate (1/2)(10) which equals 5. Now the equation is: 20 = 5t².
Step 5: Solve for t². To do this, divide both sides of the equation by 5: t² = 20 / 5, which simplifies to t² = 4.
Step 6: Find t by taking the square root of t². Since t² = 4, we take the square root: t = √4, which gives us t = 2 seconds.
Step 7: Conclude that it takes 2 seconds for the object to reach the ground.
Free Fall – The motion of an object under the influence of gravity alone, without any air resistance.
Kinematic Equations – Equations that describe the motion of objects, particularly those in free fall, relating distance, time, and acceleration.
