Science

Activity 5.1 (Page 50)   Question: What do we observe as we look through the lens? Can we draw the structures that we are able to see through the microscope, on an observation sheet? Does it look like Fig. 5.2? Answer: When we look through the lens of the microscope, we see small structures that … Read more

1 · When you look at plants, what changes do you notice as they grow? A growing plant makes new leaves and branches, becomes taller, and its stem gradually becomes thicker and stronger. 2 · What do you infer from Activity 10.1? The plant that got both sunlight and water grew best.A plant given sunlight … Read more

Activity 11.1 Questions: “• Take a tuning fork and set it vibrating by striking its prong on a rubber pad. Bring it near your ear. • Do you hear any sound? • Touch one of the prongs of the vibrating tuning fork with your finger and share your experience with your friends. • Now, suspend … Read more

In-Text Questions and Answers Question 1: A force of 7 N acts on an object. The displacement is 8 m in the direction of the force. What is the work done in this case? Answer: Work done is calculated by multiplying the force by the displacement in the direction of the force. So, Work done … Read more

Question 1: In a reaction, 5.3 g of sodium carbonate reacted with 6 g of acetic acid. The products were 2.2 g of carbon dioxide, 0.9 g of water, and 8.2 g of sodium acetate. Show that these observations are in agreement with the law of conservation of mass. Answer: Total mass of reactants: Mass … Read more

In-Text Questions and Answers What are canal rays? Answer: Canal rays are streams of positively charged particles discovered by E. Goldstein. They are also known as anode rays. These rays are produced in a gas discharge tube and move in a direction opposite to that of electrons. If an atom contains one electron and one … Read more

In-text Questions and Answers State the universal law of gravitation. Answer: The universal law of gravitation states that every object in the universe attracts every other object with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. Write the formula to … Read more

In-Text Questions Answers 1. What is a tissue? A tissue is a group of similar cells that work together to perform a specific function in an organism. This organization allows the cells to be more efficient in carrying out tasks like movement, support, or transporting nutrients. 2. What is the utility of tissues in multi-cellular … Read more

________________________________________ Activity 1.1 : Question (as per the steps in the textbook): 1. Take a 100 mL beaker. 2. Fill half the beaker with water and mark the level of water. 3. Dissolve some salt/sugar with the help of a glass rod. 4. Observe any change in water level. 5. What do you think has … Read more

1) What is meant by a substance? Answer: A substance is a form of matter that has a uniform and definite composition. It can be either an element or a compound, where all the constituent particles have the same chemical nature. 2) List the points of differences between homogeneous and heterogeneous mixtures. • Homogeneous Mixtures: … Read more