A 250 kg part falls from a plane and hits the ground at 150 km/h. Find its kinetic energy.
Would I need to convert 150km/h to m/s? then multiply with the mass?
Yes, you would need to convert the speed from kilometers per hour (km/h) to meters per second (m/s) in order to calculate the kinetic energy. Here's how you can do it step by step:
1. Convert the speed from km/h to m/s:
Since 1 km = 1000 m and 1 hour = 3600 seconds, you can convert km/h to m/s by dividing the speed in km/h by 3.6.
So, 150 km/h ÷ 3.6 = 41.67 m/s (rounded to two decimal places).
2. Calculate the kinetic energy using the formula:
The formula for kinetic energy is KE = 1/2 * mass * velocity^2.
Given the mass of the part as 250 kg and the velocity as 41.67 m/s, you can now calculate the kinetic energy.
KE = 1/2 * mass * velocity^2
= 1/2 * 250 kg * (41.67 m/s)^2
= 1/2 * 250 kg * 1736.11 m^2/s^2
≈ 216,013 J (rounded to the nearest whole number).
Therefore, the kinetic energy of the 250 kg part falling from a plane and hitting the ground at 150 km/h is approximately 216,013 joules.