https://www.khanacademy.org/science/revision-up-science-class-6-full-term/x00110b31861f2508:week-4/x00110b31861f2508:nature-s-treasures/v/water 2025-01-27T07:04:21.433023569Z Water Water scarcity is a major problem faced by over 2 Billion people across the globe. But why does this happen when 70% of the Earth's surface is made up of water? How can we help save water? Joel Prakash Stephen video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Water Water scarcity is a major problem faced by over 2 Billion people across the globe. But why does this happen when 70% of the Earth's surface is made up of water? How can we help save water? https://cdn.kastatic.org/ka-youtube-converted/Dozbgnftdao.mp4/Dozbgnftdao.mp4 254 Renewable Resources https://www.khanacademy.org/science/exam-preparation-class-6th/x196eb96f0f1caea0:week-3/x196eb96f0f1caea0:water/e/water 2026-07-28T07:40:44.245539879Z Water Let's practice! vibhor exercise https://www.khanacademy.org/science/class-7-science/x0c8b40bd4b242f0b:water/x0c8b40bd4b242f0b:hardness-and-softness-of-water/e/conserving-water 2026-03-06T17:50:38.494926415Z Conserving water Let's do some questions! vibhor exercise https://www.khanacademy.org/science/strengthened-shs-earth-and-space-science-2/x21bb710e6de17395:earth-s-surface-systems/x21bb710e6de17395:dynamics-of-hydrologic-cycle/e/groundwater-as-an-important-source-of-water 2026-05-04T07:20:44.00495003Z Groundwater as an important source of water Class 7 Science Exercise on Groundwater | NCERT Chapter 16 | Water Table, Depletion, Recharge, Tube Wells, Real-Life Applications | Conceptual Practice Questions Yajurva Joshi exercise https://www.khanacademy.org/science/up-science-grade-6-revision-course-full-term/x017c12e57b64cfa8:week-4/x017c12e57b64cfa8:untitled-260/e/hard-and-soft-water 2025-08-05T08:33:57.588913915Z Hard and soft water Hard and soft water Revathi exercise https://www.khanacademy.org/science/revision-up-science-class-6-full-term/x00110b31861f2508:week-4/x00110b31861f2508:nature-s-treasures/v/solar-energy-in 2025-06-10T18:47:28.579833154Z Solar energy Let's understand Solar energy! Dubverse video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Solar energy Let's understand Solar energy! https://cdn.kastatic.org/ka-youtube-converted/DOZZDJ36sE0.mp4/DOZZDJ36sE0.mp4 408 Renewable Resources https://www.khanacademy.org/science/cambridge-o-level-physics-cie/x0e04e0cb682fb793:energy-work-and-power/x0e04e0cb682fb793:sources-of-energy/e/using-solar-energy-energy-conservation-in-daily-life 2026-06-15T04:30:38.969568377Z Using solar energy ; Energy conservation in daily life Let's solve some problems to better understand the utilisation of solar energy and energy conservation in daily life. Aakash Bagga exercise https://www.khanacademy.org/science/cambridge-o-level-physics-cie/x0e04e0cb682fb793:energy-work-and-power/x0e04e0cb682fb793:sources-of-energy/v/windpower 2020-06-23T07:22:40Z Wind power Unlike the water-pumping windmills that inspired them, modern wind turbines generate electricity. But several engineering puzzles must still be solved to make wind power available in all communities.   NOVA video https://cdn.kastatic.org/googleusercontent/agMvP1XRZWVQbHFJOZqkoMyWKfsDUQrL94ZWKCMxLotZKfzTunEKrHcN5Tt_ZSr0ZYnWHIXheXOeo7B8Rhtkllo Wind power Unlike the water-pumping windmills that inspired them, modern wind turbines generate electricity. But several engineering puzzles must still be solved to make wind power available in all communities.   https://cdn.kastatic.org/ka-youtube-converted/SQpbTTGe_gk.mp4/SQpbTTGe_gk.mp4 154 Renewable Resources https://www.khanacademy.org/science/cambridge-o-level-physics-cie/x0e04e0cb682fb793:energy-work-and-power/x0e04e0cb682fb793:sources-of-energy/e/wind-power-quiz 2026-06-08T05:00:48.378277506Z Wind power quiz Try this quiz about wind power. NOVA exercise