Answer:
1. To calculate the kinetic energy of a 10 g paper airplane moving at 10 m/s:
Initial estimate: Since a paper airplane is very light, we can estimate that its kinetic energy will be relatively low, somewhere in the range of a few joules.
Calculation:
mass = 0.01 kg
speed = 10 m/s
Ek = 0.5 x 0.01 kg x (10 m/s)^2 = 0.5 J
Result: The actual kinetic energy is 0.5 J, which is in line with our initial estimate.
2. To calculate the kinetic energy of a 12 kg dog running at a speed of 5 m/s:
Initial estimate: Since a dog is much heavier than a paper airplane and is running at a moderate speed, we can estimate that its kinetic energy will be much higher, in the range of hundreds of joules.
Calculation:
mass = 12 kg
speed = 5 m/s
Ek = 0.5 x 12 kg x (5 m/s)^2 = 150 J
Result: The actual kinetic energy is 150 J, which is in line with our initial estimate.
3. To calculate the kinetic energy of a 65-gram sparrow flying at 12 m/s:
Initial estimate: Since a sparrow is very light and is flying at a relatively high speed, we can estimate that its kinetic energy will be moderate, in the range of a few joules.
Calculation:
mass = 0.065 kg
speed = 12 m/s
Ek = 0.5 x 0.065 kg x (12 m/s)^2 = 23.4 J
Result: The actual kinetic energy is 23.4 J, which is higher than our initial estimate but still in the same order of magnitude.
Step-by-step explanation: