AP Physics 1 Kinematics Problem #1
TLDRIn this educational video, Alan from Bothell STEM explores a kinematics problem from the AP Physics B exam. He calculates the speed and maximum height of a model rocket launched vertically, using equations for constant acceleration and gravity. Alan also offers free homework help on Twitch and Discord for those interested in math and physics.
Takeaways
- 🚀 The video is a continuation of AP Physics questions by Alan with Bothell STEM.
- 📚 They have completed all AP Physics 1 free response questions and are now using older AP Physics B exam questions.
- 🔍 The topics in AP Physics B are slightly different from AP Physics 1, so the approach is by topic rather than year.
- 📉 The video focuses on a kinematics question involving a model rocket launched vertically.
- 🔥 The rocket's engine provides an upward acceleration of 30 meters per second squared for two seconds.
- 🏔️ Upon reaching its maximum height, the rocket deploys a parachute and descends vertically to the ground.
- ⏱️ The task is to determine the speed of the rocket after two seconds of engine firing.
- 📚 The kinematic equation used is V = V₀ + acceleration * time, with initial velocity V₀ being zero.
- 📈 The rocket's velocity after two seconds is calculated to be 60 meters per second.
- 📉 The maximum height the rocket will reach is calculated in two parts: initial height gained during acceleration and additional height gained during coasting.
- 🕒 The total time to reach the maximum height is eight seconds, with two seconds of engine firing and six seconds of coasting.
Q & A
What is the main focus of the video script?
-The main focus of the video script is on solving AP Physics questions, specifically starting with a kinematics question involving a model rocket.
Why is the speaker using older questions from the AP Physics B exam?
-The speaker is using older questions from the AP Physics B exam because they have completed all of the AP Physics 1 free-response questions and need additional material to continue practicing.
What is the initial upward acceleration provided by the rocket's engine?
-The initial upward acceleration provided by the rocket's engine is 30 meters per second squared.
For how long does the rocket's engine provide acceleration?
-The rocket's engine provides acceleration for 2 seconds.
How is the speed of the rocket after two seconds of firing calculated?
-The speed of the rocket after two seconds of firing is calculated using the kinematic equation: final velocity (V) = initial velocity (V₀) + acceleration (a) × time (t). Given that V₀ is 0, a is 30 m/s², and t is 2 seconds, the final velocity is 0 + 30 × 2 = 60 meters per second.
What is the initial height reached by the rocket during the engine's firing?
-The initial height reached by the rocket during the engine's firing is calculated using the equation: Δx = V₀t + 1/2at². Given that V₀ is 0, a is 30 m/s², and t is 2 seconds, the initial height is 1/2 × 30 × 2² = 60 meters.
How is the maximum height reached by the rocket determined after the engine shuts off?
-The maximum height reached by the rocket is determined by calculating the additional height it gains while coasting upward under the influence of gravity. Using the equation VF² = V₀² + 2aΔx, where VF is 0, V₀ is 60 m/s, and a is -9.8 m/s², the additional height is Δx = 60² / (2 × 9.8) = 180 meters. The total maximum height is the sum of the initial 60 meters and the additional 180 meters, totaling 240 meters.
What is the total time taken to reach the maximum height from the launch?
-The total time taken to reach the maximum height is the sum of the 2 seconds of engine firing and the time taken to coast upward after the engine shuts off. The coasting time is calculated using the equation VF = V₀ + at, where VF is 0, V₀ is 60 m/s, and a is -9.8 m/s². The coasting time is t = 60 / 9.8 ≈ 6 seconds. Therefore, the total time is 2 + 6 = 8 seconds.
What is the significance of using older AP Physics B exam questions for practice?
-Using older AP Physics B exam questions for practice is significant because it allows students to cover a broader range of topics and problems, even though some topics might differ slightly from the current AP Physics 1 curriculum.
Where can students get additional help with their homework according to the speaker?
-Students can get additional help with their homework by joining the speaker on Twitch or Discord, where free homework help sessions are offered.
Outlines
🚀 Introduction to AP Physics B Kinematics
Alan from Bothell STEM Coach introduces the continuation of AP Physics questions, shifting from AP Physics 1 to older AP Physics B exam questions. He notes the differences between the two exams and decides to tackle the topics by category rather than by year. The video focuses on a kinematics problem involving a model rocket launched vertically with a detailed step-by-step solution.
📏 Solving the Kinematics Problem
Alan solves a kinematics problem where a model rocket is launched vertically. He first calculates the rocket's speed after two seconds of engine firing, using the equation for constant acceleration. He then determines the maximum height reached by splitting the problem into two parts: the initial ascent with engine power and the subsequent ascent under gravity. By applying kinematic equations, he finds the total height and time taken to reach it. Finally, Alan summarizes the process and invites viewers to seek homework help on Twitch or Discord.
Mindmap
Keywords
💡AP Physics
💡Kinematics
💡Acceleration
💡Velocity
💡Maximum Height
💡Free Response Questions
💡Initial Velocity
💡Constant Acceleration
💡Gravity
💡Parachute Deployment
Highlights
Alan introduces the continuation of AP Physics questions.
Completed all AP Physics one free response questions.
Transitioning to older AP Physics B exam questions due to differences in topics.
Approach to tackle questions topic by topic rather than year by year.
Introduction of a kinematics question involving a model rocket.
Rocket launched vertically with an engine ignition at time T equals zero.
Engine provides upward acceleration of 30 meters per second squared for two seconds.
Rocket deploys a parachute upon reaching maximum height.
Objective is to determine the speed of the rocket after two seconds of engine firing.
Use of kinematic equation to calculate final velocity under constant acceleration.
Calculation of initial height gained during the first two seconds of launch.
Determination of maximum height using the equation VF squared equals V naught squared plus 2a Delta X.
Explanation of the rocket's motion under gravity after engine shutdown.
Calculation of total height reached by the rocket combining initial and subsequent heights.
Determination of time to reach maximum height using the equation relating initial and final velocities and acceleration.
Total time calculation from engine ignition to reaching maximum height.
Alan offers free homework help on Twitch or Discord for further assistance.
Transcripts
5.0 / 5 (0 votes)
Thanks for rating: