A 1 kg mass is dropped from a height of 1 m. What is its speed just before it hi
Practice Questions
Q1
A 1 kg mass is dropped from a height of 1 m. What is its speed just before it hits the ground?
1 m/s
2 m/s
3 m/s
4 m/s
Questions & Step-by-Step Solutions
A 1 kg mass is dropped from a height of 1 m. What is its speed just before it hits the ground?
Correct Answer: 4.43 m/s
Step 1: Understand that when the mass is dropped, it has potential energy due to its height.
Step 2: Recognize that as it falls, this potential energy converts to kinetic energy, which is the energy of motion.
Step 3: Use the formula for speed just before hitting the ground, which is derived from the conservation of energy: v = √(2gh).
Step 4: Identify the values: g (acceleration due to gravity) is approximately 9.8 m/s², and h (height) is 1 m.
Step 5: Plug the values into the formula: v = √(2 * 9.8 * 1).
Step 6: Calculate the value: v = √(19.6).
Step 7: Find the square root of 19.6, which is approximately 4.43 m/s.
Conservation of Energy – The principle that the total energy in a closed system remains constant; in this case, gravitational potential energy is converted to kinetic energy.
Kinematics – The study of motion, specifically how the speed of an object changes under the influence of gravity.
