A ball is dropped from a height of 80 m. How long will it take to reach the grou
Practice Questions
Q1
A ball is dropped from a height of 80 m. How long will it take to reach the ground? (Assume g = 10 m/s²)
4 s
5 s
6 s
8 s
Questions & Step-by-Step Solutions
A ball is dropped from a height of 80 m. How long will it take to reach the ground? (Assume g = 10 m/s²)
Step 1: Identify the height from which the ball is dropped. In this case, the height (h) is 80 meters.
Step 2: Identify the acceleration due to gravity (g). Here, g is given as 10 m/s².
Step 3: Use the formula for the distance fallen under gravity: h = 0.5 * g * t².
Step 4: Substitute the known values into the formula: 80 = 0.5 * 10 * t².
Step 5: Simplify the equation: 80 = 5 * t².
Step 6: Divide both sides by 5 to isolate t²: t² = 80 / 5, which gives t² = 16.
Step 7: Take the square root of both sides to find t: t = √16, which gives t = 4 seconds.
Kinematics – The question tests understanding of the equations of motion, specifically how to calculate the time of free fall using the height and acceleration due to gravity.
Free Fall – It assesses knowledge of free fall motion under the influence of gravity, where the only force acting on the object is gravity.