OwlSheets Students
← Exit

Launch Day Altimeter Log: Height and Stored Energy

0 / 11

Launch Day Altimeter Log: Height and Stored Energy

Use a model rocket's flight log to model how distance from Earth changes stored energy.

Part 1: The Kestrel's flight log

Read the launch day notes and study the flight log. Then answer the questions.

Launch Day at the Sod Farm

1On the first Saturday in May, the Harlow Flats Rocket Club met at a grassy sod farm outside town for launch day. Eighth grader Kalani Brandt had built the club's newest rocket, the Kestrel, and fitted it with a small altimeter, a device that records the rocket's height above the ground several times each second. Club advisor Ms. Yevgenia Torres asked the members to use the altimeter data to model how energy is stored as the rocket moves away from Earth and back again.

2Ms. Torres explained that the rocket and Earth pull on each other even when they are not touching, so together they form a system. Potential energy is stored in this system, and the amount depends on the distance between the rocket and Earth. Near Earth's surface, Earth pulls on each kilogram with a force of about 10 N, so the energy stored compared with the ground is: stored energy (J) = mass (kg) × 10 × height (m). After its motor burns out, the Kestrel has a mass of 0.25 kg, so each meter of height adds 2.5 J.

3Ms. Torres launched the Kestrel from a launch pad at the center of the field while everyone stood well back. The motor burned for 1.5 s and pushed the rocket up to 40 m. After that, the rocket coasted upward, slowing down the whole way, until it reached its highest point. There a small charge pushed out a parachute, and the rocket drifted slowly back down. It landed in the grass about 50 s after liftoff, and Kalani downloaded the log to the club's laptop.

4Later that afternoon, the club launched the Osprey, a wider rocket with a heavier camera inside. After its motor burned out, the Osprey had a mass of 0.50 kg. Its altimeter showed that it reached a highest point of only 80 m.

5While the club packed up, member Ana Lucero tried a different system. She rubbed two plastic streamers with a wool cloth, which gave both streamers the same kind of electric charge, and hung them side by side from the launch rod. The streamers pushed each other apart without touching. When Ana pinched their ends together and let go, they sprang apart. The closer together she pinched them, the faster they sprang apart.

Kestrel Flight Log (stored energy compared with the ground)
MomentTime (s)Height (m)Stored energy (J)
A: On the pad000
B: Motor burns out1.540100
C: Highest point6.0160?
D: Parachute open8.0140350
E: Drifting down2580200
F: Landing5000
1.
Use the formula in paragraph 2 to find the missing value in the flight log.

At moment C, the rocket–Earth system stored J compared with the ground.

2.
Use paragraph 3 and the flight log. At which moment was the most energy stored in the rocket–Earth system?
Question 2 options
3.
Use the flight log. The rocket drifted from moment C down to moment E.

The energy stored in the rocket–Earth system went down by J.

4.
Use the flight log. Between moment E and moment F, the rocket drifted down under its parachute for 25 s.

On average, the stored energy went down by J each second.

5.
Which statement best describes how the stored energy changes with height in the flight log?
Question 5 options

Part 2: Two rockets and two streamers

Use paragraphs 2, 4 and 5 and the flight log to answer the questions.

6.
Use paragraphs 2 and 4.

At its highest point, the Osprey–Earth system stored J compared with the ground.

7.
Compare the two rockets at their highest points. Which statement is correct?
Question 7 options
8.
Kalani wants the Kestrel (0.25 kg) to reach a height where the rocket–Earth system stores 500 J compared with the ground.

The Kestrel would need to reach a height of m.

9.
Use the passage and the flight log. Sort each change by what happens to the potential energy stored in the system named.
10.
The rocket and Earth attract each other, but Ana's streamers repel each other. Which model fits both systems in the passage?
Question 10 options
11.
A club member says, "The Kestrel–Earth system stored the most energy at moment B, because that is when the rocket was moving fastest." Do you agree? Write a claim, give evidence from the flight log and paragraph 3, and explain your reasoning about what stored energy in the rocket–Earth system depends on.