🧲 Physics

Read this aloud (it is the lesson's hook). Students think, then tell a partner what they notice.

“A runner's GPS app graphs distance over time. The slope is the speed.”

1. Open the lesson link on the board.
2. Press Next to the 🎬 Watch in 3D step and press ▶ Play. Students can drag to turn the model. This lesson has 2 3D videos in a row: press Next and ▶ Play for each part.
3. Press Next to the Movie step and press ▶ Play.

The video says:

• Walk 3 meters forward, then 3 meters back. Distance is the whole path, 6 meters. Displacement is the change in position: 0.
• This cart moves at a steady 2 meters per second. On a position-time graph, that makes a straight line. Its slope is the velocity.
• A faster cart makes a steeper line. Steeper means faster.
• A cart that does not move makes a flat line. Flat means at rest.
• A line that slopes down means the cart moves backward: negative velocity.

Students open the same lesson on their own device (or work with the board). Press Next to Try it.

Try it together first:

🧱 Build it: the lesson's short 3D build game. Let students play it after Try it. Its score never changes grades.

If time is left, students play the lesson's game steps (they show up between the videos and Check).

Students press Next to Check and answer the 4 questions on their own device. Goal: 100%. 95% or more is Mastered. “Not yet” means try again; students may retry.

Read this question aloud. Students write the answer on a slip of paper with no name or with a class number, and hand it in.

Read this aloud (it is the lesson's hook). Students think, then tell a partner what they notice.

“A car speeds from 0 to 30 m/s in 6 s. That's acceleration; F = ma tells the force.”

1. Open the lesson link on the board.
2. Press Next to the 🎬 Watch in 3D step and press ▶ Play. Students can drag to turn the model. This lesson has 3 3D videos in a row: press Next and ▶ Play for each part.
3. Press Next to the Movie step and press ▶ Play.

The video says:

• Newton's first law: with no net force, an object at rest stays at rest, and a moving object keeps moving at the same velocity. That is inertia.
• Two equal pushes in opposite directions are balanced. The net force is zero, so the motion does not change.
• Newton's second law: an unbalanced force makes an object accelerate. 20 newtons on 10 kilograms gives 2 meters per second squared.
• Double the force, and the acceleration doubles: 4 meters per second squared.
• Double the mass instead, and the acceleration is cut in half: 1 meter per second squared. F equals m a.

Students open the same lesson on their own device (or work with the board). Press Next to Try it.

Try it together first:

🧱 Build it: the lesson's short 3D build game. Let students play it after Try it. Its score never changes grades.

If time is left, students play the lesson's game steps (they show up between the videos and Check).

Students press Next to Check and answer the 4 questions on their own device. Goal: 100%. 95% or more is Mastered. “Not yet” means try again; students may retry.

Read this question aloud. Students write the answer on a slip of paper with no name or with a class number, and hand it in.

Read this aloud (it is the lesson's hook). Students think, then tell a partner what they notice.

“Drop a ball from a balcony: gravity speeds it up by about 10 m/s every second.”

1. Open the lesson link on the board.
2. Press Next to the 🎬 Watch in 3D step and press ▶ Play. Students can drag to turn the model. This lesson has 3 3D videos in a row: press Next and ▶ Play for each part.
3. Press Next to the Movie step and press ▶ Play.

The video says:

• Drop a ball. Gravity makes it speed up by about 9.8 meters per second, every second.
• Snapshots one second apart: the ball falls 4.9 meters in the first second, but much farther in each second after.
• Its speed grows the same amount each second: 9.8, then 19.6, then 29.4 meters per second. That steady change is the acceleration g.
• With the air pumped out, a hammer and a feather fall together. Without air, all objects fall with the same acceleration.
• With air, air resistance slows the light, wide feather much more than the hammer.

Students open the same lesson on their own device (or work with the board). Press Next to Try it.

Try it together first:

🧱 Build it: the lesson's short 3D build game. Let students play it after Try it. Its score never changes grades.

If time is left, students play the lesson's game steps (they show up between the videos and Check).

Students press Next to Check and answer the 4 questions on their own device. Goal: 100%. 95% or more is Mastered. “Not yet” means try again; students may retry.

Read this question aloud. Students write the answer on a slip of paper with no name or with a class number, and hand it in.

Read this aloud (it is the lesson's hook). Students think, then tell a partner what they notice.

“In tug-of-war, the net force decides which way the rope moves.”

1. Open the lesson link on the board.
2. Press Next to the 🎬 Watch in 3D step and press ▶ Play. Students can drag to turn the model. This lesson has 2 3D videos in a row: press Next and ▶ Play for each part.
3. Press Next to the Movie step and press ▶ Play.

The video says:

• This 10 kilogram crate slides to the right. Gravity pulls it down with its weight: m g, 10 times 9.8, which is 98 newtons.
• The floor pushes up with the normal force, 98 newtons. Up and down balance.
• Someone pushes it to the right with 50 newtons.
• Friction acts against the sliding: 30 newtons to the left.
• Add the forces: 50 right minus 30 left is a net force of 20 newtons to the right. So a equals 20 divided by 10, which is 2 meters per second squared.

Students open the same lesson on their own device (or work with the board). Press Next to Try it.

Try it together first:

🧱 Build it: the lesson's short 3D build game. Let students play it after Try it. Its score never changes grades.

If time is left, students play the lesson's game steps (they show up between the videos and Check).

Students press Next to Check and answer the 4 questions on their own device. Goal: 100%. 95% or more is Mastered. “Not yet” means try again; students may retry.

Read this question aloud. Students write the answer on a slip of paper with no name or with a class number, and hand it in.

Read this aloud (it is the lesson's hook). Students think, then tell a partner what they notice.

“A basketball shot curves because it moves sideways at a steady speed while gravity pulls it down.”

1. Open the lesson link on the board.
2. Press Next to the 🎬 Watch in 3D step and press ▶ Play. Students can drag to turn the model. This lesson has 2 3D videos in a row: press Next and ▶ Play for each part.
3. Press Next to the Movie step and press ▶ Play.

The video says:

• One ball is dropped. The other is thrown sideways at the same moment. Watch their heights: they always match, and they land together.
• A projectile has two separate motions: a steady sideways velocity, and a downward velocity that grows by 9.8 meters per second each second.
• The floor shadow moves in equal steps. The wall shadow moves in bigger and bigger steps.
• The fall time depends only on the height: about 1.43 seconds from 10 meters. At 5 meters per second sideways, it lands about 7.1 meters away.

Students open the same lesson on their own device (or work with the board). Press Next to Try it.

Try it together first:

🧱 Build it: the lesson's short 3D build game. Let students play it after Try it. Its score never changes grades.

If time is left, students play the lesson's game steps (they show up between the videos and Check).

Students press Next to Check and answer the 4 questions on their own device. Goal: 100%. 95% or more is Mastered. “Not yet” means try again; students may retry.

Read this question aloud. Students write the answer on a slip of paper with no name or with a class number, and hand it in.

Read this aloud (it is the lesson's hook). Students think, then tell a partner what they notice.

“On a merry-go-round you feel pushed outward, but the real force pulls you inward.”

1. Open the lesson link on the board.
2. Press Next to the 🎬 Watch in 3D step and press ▶ Play. Students can drag to turn the model. This lesson has 2 3D videos in a row: press Next and ▶ Play for each part.
3. Press Next to the Movie step and press ▶ Play.

The video says:

• A puck on a string slides in a circle at a steady speed.
• Its velocity points along the circle, so its direction keeps changing. Changing direction means it is accelerating.
• That needs a force toward the center: the centripetal force. Here, the string pulls inward.
• Cut the string, and the puck moves off in a straight line, along the direction it was going.
• On a merry-go-round, the real force on you points inward. The outward feeling is just your inertia.

Students open the same lesson on their own device (or work with the board). Press Next to Try it.

Try it together first:

🧱 Build it: the lesson's short 3D build game. Let students play it after Try it. Its score never changes grades.

If time is left, students play the lesson's game steps (they show up between the videos and Check).

Students press Next to Check and answer the 4 questions on their own device. Goal: 100%. 95% or more is Mastered. “Not yet” means try again; students may retry.

Read this question aloud. Students write the answer on a slip of paper with no name or with a class number, and hand it in.

Read this aloud (it is the lesson's hook). Students think, then tell a partner what they notice.

“The same gravity that drops an apple keeps the Moon in orbit.”

1. Open the lesson link on the board.
2. Press Next to the 🎬 Watch in 3D step and press ▶ Play. Students can drag to turn the model. This lesson has 2 3D videos in a row: press Next and ▶ Play for each part.
3. Press Next to the Movie step and press ▶ Play.

The video says:

• Any two masses pull on each other with gravity. The forces are equal in size and opposite in direction.
• Double one of the masses, and the force doubles.
• Double both masses, and the force becomes 4 times as big.
• Double the distance, and the force drops to one fourth.
• Newton's law of gravitation: F equals G m1 m2 over r squared. The same pull that drops an apple keeps the Moon in orbit.

Students open the same lesson on their own device (or work with the board). Press Next to Try it.

Try it together first:

🧱 Build it: the lesson's short 3D build game. Let students play it after Try it. Its score never changes grades.

If time is left, students play the lesson's game steps (they show up between the videos and Check).

Students press Next to Check and answer the 4 questions on their own device. Goal: 100%. 95% or more is Mastered. “Not yet” means try again; students may retry.

Read this question aloud. Students write the answer on a slip of paper with no name or with a class number, and hand it in.

Read this aloud (it is the lesson's hook). Students think, then tell a partner what they notice.

“Airbags lengthen collision time to reduce force.”

1. Open the lesson link on the board.
2. Press Next to the 🎬 Watch in 3D step and press ▶ Play. Students can drag to turn the model. This lesson has 2 3D videos in a row: press Next and ▶ Play for each part.
3. Press Next to the Movie step and press ▶ Play.

The video says:

• Momentum is mass times velocity. A 2 kilogram cart at 3 meters per second has 6 kilogram meters per second of momentum.
• It hits a 1 kilogram cart at rest, and they stick. The 6 units of momentum are now shared by 3 kilograms, so they move at 2 meters per second.
• Total momentum before the collision equals total momentum after. Momentum is conserved.
• Two equal carts in a bouncy collision: the first one stops, and the second leaves with all the momentum.
• Two carts at rest push apart. Their momenta are equal and opposite, so the total stays zero.

Students open the same lesson on their own device (or work with the board). Press Next to Try it.

Try it together first:

🧱 Build it: the lesson's short 3D build game. Let students play it after Try it. Its score never changes grades.

If time is left, students play the lesson's game steps (they show up between the videos and Check).

Students press Next to Check and answer the 4 questions on their own device. Goal: 100%. 95% or more is Mastered. “Not yet” means try again; students may retry.

Read this question aloud. Students write the answer on a slip of paper with no name or with a class number, and hand it in.

Read this aloud (it is the lesson's hook). Students think, then tell a partner what they notice.

“A roller coaster trades height for speed.”

1. Open the lesson link on the board.
2. Press Next to the 🎬 Watch in 3D step and press ▶ Play. Students can drag to turn the model. This lesson has 3 3D videos in a row: press Next and ▶ Play for each part.
3. Press Next to the Movie step and press ▶ Play.

The video says:

• At the top of the first hill, the coaster car is barely moving. Its energy is almost all gravitational potential energy, m g h.
• As it rolls down, potential energy turns into kinetic energy. Watch the bars: the total stays the same.
• At the lowest point, it is all kinetic energy. From 20 meters, the speed is about 19.8 meters per second.
• On the 10 meter hill, half of the energy is potential and half is kinetic.
• With friction, some energy becomes thermal energy. The total is still conserved, but the car can't get back to its starting height.

Students open the same lesson on their own device (or work with the board). Press Next to Try it.

Try it together first:

🧱 Build it: the lesson's short 3D build game. Let students play it after Try it. Its score never changes grades.

If time is left, students play the lesson's game steps (they show up between the videos and Check).

Students press Next to Check and answer the 4 questions on their own device. Goal: 100%. 95% or more is Mastered. “Not yet” means try again; students may retry.

Read this question aloud. Students write the answer on a slip of paper with no name or with a class number, and hand it in.

Read this aloud (it is the lesson's hook). Students think, then tell a partner what they notice.

“An LED bulb turns more of its electrical energy into light than an old incandescent bulb.”

1. Open the lesson link on the board.
2. Press Next to the 🎬 Watch in 3D step and press ▶ Play. Students can drag to turn the model. This lesson has 2 3D videos in a row: press Next and ▶ Play for each part.
3. Press Next to the Movie step and press ▶ Play.

The video says:

• Every device changes energy from one form to another. 100 joules of electrical energy go into this old-style bulb.
• Only about 10 joules come out as light. About 90 joules become heat.
• Efficiency is useful energy out divided by energy in: 10 divided by 100 is 10 percent.
• No energy is lost from the universe: 100 joules in equals 10 joules of light plus 90 joules of heat.
• An LED makes the same light with about a quarter of the energy, so far less is wasted as heat.

Students open the same lesson on their own device (or work with the board). Press Next to Try it.

Try it together first:

🧱 Build it: the lesson's short 3D build game. Let students play it after Try it. Its score never changes grades.

If time is left, students play the lesson's game steps (they show up between the videos and Check).

Students press Next to Check and answer the 4 questions on their own device. Goal: 100%. 95% or more is Mastered. “Not yet” means try again; students may retry.

Read this question aloud. Students write the answer on a slip of paper with no name or with a class number, and hand it in.

Read this aloud (it is the lesson's hook). Students think, then tell a partner what they notice.

“Ice in lemonade melts as heat flows from the warm drink into the cold ice.”

1. Open the lesson link on the board.
2. Press Next to the 🎬 Watch in 3D step and press ▶ Play. Students can drag to turn the model. This lesson has 2 3D videos in a row: press Next and ▶ Play for each part.
3. Press Next to the Movie step and press ▶ Play.

The video says:

• Temperature measures how fast particles move. Hot particles jiggle faster than cold ones.
• When a hot block touches a cold block, energy flows from hot to cold. That energy flow is heat.
• The flow stops when both reach the same temperature. That is thermal equilibrium.
• Heat moves three ways: conduction through touching particles, convection in moving fluids, and radiation as waves.
• Ice in lemonade melts because heat flows from the warm drink into the cold ice, not because cold flows out of the ice.

Students open the same lesson on their own device (or work with the board). Press Next to Try it.

Try it together first:

🧱 Build it: the lesson's short 3D build game. Let students play it after Try it. Its score never changes grades.

If time is left, students play the lesson's game steps (they show up between the videos and Check).

Students press Next to Check and answer the 4 questions on their own device. Goal: 100%. 95% or more is Mastered. “Not yet” means try again; students may retry.

Read this question aloud. Students write the answer on a slip of paper with no name or with a class number, and hand it in.

Read this aloud (it is the lesson's hook). Students think, then tell a partner what they notice.

“String lights wired in parallel stay lit when one bulb burns out.”

1. Open the lesson link on the board.
2. Press Next to the 🎬 Watch in 3D step and press ▶ Play. Students can drag to turn the model. This lesson has 3 3D videos in a row: press Next and ▶ Play for each part.
3. Press Next to the Movie step and press ▶ Play.

The video says:

• A circuit is a closed loop. Current flows from the battery, through the bulb, and back to the battery.
• Open the switch and the loop is broken. No current flows, so the bulb goes out.
• In a series circuit there is only one path. Two 6 ohm bulbs on 6 volts share the voltage, so the current is 0.5 amps and both glow dimmer.
• Remove one bulb from a series circuit, and the only path is broken: every bulb goes dark.
• In a parallel circuit, each bulb has its own path and gets the full 6 volts. Each branch carries 1 amp, so the total is 2 amps.

Students open the same lesson on their own device (or work with the board). Press Next to Try it.

Try it together first:

🧱 Build it: the lesson's short 3D build game. Let students play it after Try it. Its score never changes grades.

If time is left, students play the lesson's game steps (they show up between the videos and Check).

Students press Next to Check and answer the 4 questions on their own device. Goal: 100%. 95% or more is Mastered. “Not yet” means try again; students may retry.

Read this question aloud. Students write the answer on a slip of paper with no name or with a class number, and hand it in.

Read this aloud (it is the lesson's hook). Students think, then tell a partner what they notice.

“Generators spin magnets near coils to make electricity.”

1. Open the lesson link on the board.
2. Press Next to the 🎬 Watch in 3D step and press ▶ Play. Students can drag to turn the model. This lesson has 3 3D videos in a row: press Next and ▶ Play for each part.
3. Press Next to the Movie step and press ▶ Play.

The video says:

• Electric charges come in two kinds. Like charges push each other apart.
• Opposite charges pull together.
• Coulomb's law: the force grows with the charges and weakens with distance squared, just like gravity.
• A charge makes an electric field around it. Field lines point away from a positive charge.
• Moving charges make magnetic fields. Current in a wire makes a magnetic field that circles the wire, and compass needles line up with it.

Students open the same lesson on their own device (or work with the board). Press Next to Try it.

Try it together first:

🧱 Build it: the lesson's short 3D build game. Let students play it after Try it. Its score never changes grades.

If time is left, students play the lesson's game steps (they show up between the videos and Check).

Students press Next to Check and answer the 4 questions on their own device. Goal: 100%. 95% or more is Mastered. “Not yet” means try again; students may retry.

Read this question aloud. Students write the answer on a slip of paper with no name or with a class number, and hand it in.

Read this aloud (it is the lesson's hook). Students think, then tell a partner what they notice.

“Wi-Fi, X-rays and visible light are all electromagnetic waves.”

1. Open the lesson link on the board.
2. Press Next to the 🎬 Watch in 3D step and press ▶ Play. Students can drag to turn the model. This lesson has 2 3D videos in a row: press Next and ▶ Play for each part.
3. Press Next to the Movie step and press ▶ Play.

The video says:

• A wave carries energy from place to place. Watch the red bead: it only moves up and down, while the wave moves along.
• The high points are crests and the bottom points are troughs. The amplitude is the height from the middle. One wavelength is crest to crest.
• Frequency is how many waves pass each second. At the same speed, double the frequency gives half the wavelength.
• Wave speed equals frequency times wavelength: 2 hertz times 1.5 meters is 3 meters per second.
• In a longitudinal wave, like sound, the coils move back and forth along the direction the wave travels.

Students open the same lesson on their own device (or work with the board). Press Next to Try it.

Try it together first:

🧱 Build it: the lesson's short 3D build game. Let students play it after Try it. Its score never changes grades.

If time is left, students play the lesson's game steps (they show up between the videos and Check).

Students press Next to Check and answer the 4 questions on their own device. Goal: 100%. 95% or more is Mastered. “Not yet” means try again; students may retry.

Read this question aloud. Students write the answer on a slip of paper with no name or with a class number, and hand it in.

Read this aloud (it is the lesson's hook). Students think, then tell a partner what they notice.

“An ambulance siren sounds higher as it comes toward you and deeper as it drives away: the Doppler effect.”

1. Open the lesson link on the board.
2. Press Next to the 🎬 Watch in 3D step and press ▶ Play. Students can drag to turn the model. This lesson has 2 3D videos in a row: press Next and ▶ Play for each part.
3. Press Next to the Movie step and press ▶ Play.

The video says:

• Reflection: a wave bounces off a surface. The angle in equals the angle out, measured from the normal line.
• Refraction: light slows down when it enters glass, so it bends toward the normal.
• Diffraction: waves spread out after they pass through a gap or around an edge.
• Interference: where two crests meet, the waves add up. Where a crest meets a trough, they cancel.

Students open the same lesson on their own device (or work with the board). Press Next to Try it.

Try it together first:

🧱 Build it: the lesson's short 3D build game. Let students play it after Try it. Its score never changes grades.

If time is left, students play the lesson's game steps (they show up between the videos and Check).

Students press Next to Check and answer the 4 questions on their own device. Goal: 100%. 95% or more is Mastered. “Not yet” means try again; students may retry.

Read this question aloud. Students write the answer on a slip of paper with no name or with a class number, and hand it in.

Read this aloud (it is the lesson's hook). Students think, then tell a partner what they notice.

“UV light can cause sunburn but radio waves can't: each UV photon carries more energy.”

1. Open the lesson link on the board.
2. Press Next to the 🎬 Watch in 3D step and press ▶ Play. Students can drag to turn the model. This lesson has 2 3D videos in a row: press Next and ▶ Play for each part.
3. Press Next to the Movie step and press ▶ Play.

The video says:

• Light travels as an electromagnetic wave. It reflects, refracts, diffracts and interferes like other waves.
• But light also arrives in tiny packets of energy called photons.
• A photon's energy depends on its frequency: E equals h f. Blue photons carry more energy than red ones, and ultraviolet even more.
• Send photons through two slits one at a time. Each lands as a dot, but together they build interference bands. Light acts as both a wave and a particle.
• That is why ultraviolet light can cause sunburn but radio waves can't: each UV photon carries much more energy.

Students open the same lesson on their own device (or work with the board). Press Next to Try it.

Try it together first:

🧱 Build it: the lesson's short 3D build game. Let students play it after Try it. Its score never changes grades.

If time is left, students play the lesson's game steps (they show up between the videos and Check).

Students press Next to Check and answer the 4 questions on their own device. Goal: 100%. 95% or more is Mastered. “Not yet” means try again; students may retry.

Read this question aloud. Students write the answer on a slip of paper with no name or with a class number, and hand it in.

Read this aloud (it is the lesson's hook). Students think, then tell a partner what they notice.

“Your phone sends photos as digital signals: patterns of 1s and 0s carried by radio waves.”

1. Open the lesson link on the board.
2. Press Next to the 🎬 Watch in 3D step and press ▶ Play. Students can drag to turn the model. This lesson has 2 3D videos in a row: press Next and ▶ Play for each part.
3. Press Next to the Movie step and press ▶ Play.

The video says:

• An analog signal changes smoothly and can have any value.
• A digital signal uses only two levels: 1 and 0.
• As signals travel, noise sneaks in. The analog signal's shape gets changed, and that error can't be easily removed.
• The digital signal is easy to repair: anything above the cut-off is read as 1, anything below as 0, so the message gets through.
• Your phone sends those 1s and 0s on radio waves. Big waves mean 1, small waves mean 0.

Students open the same lesson on their own device (or work with the board). Press Next to Try it.

Try it together first:

🧱 Build it: the lesson's short 3D build game. Let students play it after Try it. Its score never changes grades.

If time is left, students play the lesson's game steps (they show up between the videos and Check).

Students press Next to Check and answer the 4 questions on their own device. Goal: 100%. 95% or more is Mastered. “Not yet” means try again; students may retry.

Read this question aloud. Students write the answer on a slip of paper with no name or with a class number, and hand it in.

Read this aloud (it is the lesson's hook). Students think, then tell a partner what they notice.

“Carbon-14 dating tells the age of ancient wood and bone.”

1. Open the lesson link on the board.
2. Press Next to the 🎬 Watch in 3D step and press ▶ Play. Students can drag to turn the model. This lesson has 3 3D videos in a row: press Next and ▶ Play for each part.
3. Press Next to the Movie step and press ▶ Play.

The video says:

• These 64 nuclei are unstable. No one can say which will decay next, but the group follows a steady rule.
• After one half-life, half of them have decayed: 32 are left.
• After two half-lives, half of those decay too: 16 left, or 25 percent.
• After three half-lives: 8 left, 12.5 percent. The graph curves down but never quite reaches zero.
• Carbon-14 has a half-life of about 5,730 years. Ancient wood with 25 percent of its carbon-14 left is about 11,460 years old.

Students open the same lesson on their own device (or work with the board). Press Next to Try it.

Try it together first:

🧱 Build it: the lesson's short 3D build game. Let students play it after Try it. Its score never changes grades.

If time is left, students play the lesson's game steps (they show up between the videos and Check).

Students press Next to Check and answer the 4 questions on their own device. Goal: 100%. 95% or more is Mastered. “Not yet” means try again; students may retry.

Read this question aloud. Students write the answer on a slip of paper with no name or with a class number, and hand it in.