A 2 kg object is dropped from a height of 20 m. What is its speed just before it
Practice Questions
Q1
A 2 kg object is dropped from a height of 20 m. What is its speed just before it hits the ground? (g = 10 m/s²) (2023)
20 m/s
10 m/s
15 m/s
5 m/s
Questions & Step-by-Step Solutions
A 2 kg object is dropped from a height of 20 m. What is its speed just before it hits the ground? (g = 10 m/s²) (2023)
Step 1: Identify the given values. The mass of the object is 2 kg, the height from which it is dropped is 20 m, and the acceleration due to gravity (g) is 10 m/s².
Step 2: Write down the formula to find the speed just before hitting the ground. The formula is v = √(2gh).
Step 3: Substitute the values into the formula. Replace g with 10 m/s² and h with 20 m: v = √(2 * 10 m/s² * 20 m).
Step 4: Calculate the value inside the square root. First, calculate 2 * 10 = 20, then multiply by 20 m: 20 * 20 = 400.
Step 5: Now, take the square root of 400. √400 = 20.
Step 6: The final answer is that the speed of the object just before it hits the ground is 20 m/s.
Kinematics – The question tests the understanding of the kinematic equations related to free fall and the calculation of final velocity.
Gravitational Acceleration – It assesses the knowledge of gravitational acceleration and its effect on falling objects.