Physics Lab
Every section runs the same four-stage loop: read the idea → see it move → solve problems → check yourself. Simulations you can drag, problems that reveal one step at a time, and progress saved on your own device.
Relative velocity
Sections 20.1–22 · four stages · 24 problems · 6 self-checks
The rule
V(XY) = V(X) − V(Y)
Same direction, opposite direction, and why swapping the viewer flips the sign — plus the four-step method and the mistakes to avoid.
#the-rule · #four-step-method Read Stage 2 · See it moveFour live simulators
Seats, angles, rivers, rain
Change your seat in a moving car, build relative velocity at an angle, cross a river three ways, and tilt an umbrella into the rain.
#change-your-seat · #at-an-angle · #river-boat · #rain-problems See Stage 3 · Solve24 problems in six levels
Warm-up → angles → river–boat → rain → challenge
Each solution stays hidden until you ask for the next step, so you can compare it against your own working.
#level-1-warm-up … #level-6-challenge Try Stage 4 · CheckSelf-check
Six questions with instant feedback
Directions, the angle formula, shortest-time crossings and the umbrella tilt — with the reason behind every answer.
#check-yourself CheckHow this lab is built
Same loop everywhere, progress kept on your device
Stages, not chapters
Start anywhere. The sticky rail at the top tracks the four stages, and each section keeps its own tick, so you can leave mid-way and come back later.
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Ticks, self-check answers and the theme you picked live in your browser only. Use “reset this lab” in the footer for a clean run.
Offline-readyChemistry Lab →
SSC রসায়ন · অধ্যায় ৬
রাসায়নিক বিক্রিয়া ও সমীকরণ — ৮টি সেকশন, একই লুপে: পড়ো → দেখো → নিজে করো → যাচাই।
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