1. (b) As the object is moving on a frictionless horizontal surface with a constant velocity of 4 m s¯¹, its acceleration is zero and hence no force is acting on the given object. https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-8/

    (b) As the object is moving on a frictionless horizontal surface with a constant velocity of 4 m s¯¹, its acceleration is zero and hence no force is acting on the given object.

    https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-8/

    See less
    • 25
  2. (b) As the athlete completes one round of a circular track in 40 s, hence in 2 min 20 s (or 140s) he will complete 7/2 rounds. Thus as shown in figure if he starts running from point A then on completion of 7/2 round he will be at point B. Thus, net displacement of the athlete AB = 2R. https://www.tRead more

    (b) As the athlete completes one round of a circular track in 40 s, hence in 2 min 20 s (or 140s) he will complete 7/2 rounds. Thus as shown in figure if he starts running from point A then on completion of 7/2 round he will be at point B. Thus, net displacement of the athlete AB = 2R.

    https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-7/

    See less
    • 28
  3. (c) Viruses behave as non-living outside the cells of host. https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-5/

    (c) Viruses behave as non-living outside the cells of host.

    https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-5/

    See less
    • 14
  4. The correct answer is (c) Evaporation, diffusion, expansion of gases. Increasing temperature enhances evaporation by providing more energy to molecules, diffusion by increasing molecular motion, and expansion of gases due to increased kinetic energy, causing gases to occupy more volume. https://www.Read more

    The correct answer is (c) Evaporation, diffusion, expansion of gases.
    Increasing temperature enhances evaporation by providing more energy to molecules, diffusion by increasing molecular motion, and expansion of gases due to increased kinetic energy, causing gases to occupy more volume.

    https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-1/

    See less
    • 27
  5. (d) Starch grains are manufactured in chloroplast during photosynthesis. Hormones are manufactured by endocrine glands. Ribosomes are site of protein synthesis and chemically all enzymes are proteins. https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-5/

    (d) Starch grains are manufactured in chloroplast during photosynthesis. Hormones are manufactured by endocrine glands. Ribosomes are site of protein synthesis and chemically all enzymes are proteins.

    https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-5/

    See less
    • 18