QUES: What if two children push a swing at the same time? Would the swing go higher? Yes, together their force would be more. It is common for forces to be combined. Most objects on Earth have at least two forces acting on them. Do you know what one of them is? Of course, that force is gravity. How many forces do you have on you right now? Gravity pulls you down toward the center of Earth. Your legs exert a downward force. They hold you up against the pull of gravity. Consider the example in Figure 1.3. A book is resting on a table. Gravity pulls the book downward. It has a force of 20 newtons. At the same time, the table pushes the book upward. Its force is also 20 newtons. The table opposes the pull of gravity.
Do you have any questions?
MY QUESTION: Give two examples of combined forces action on an object

QUES: The opening shot of the movie shows Kunti praying for Lord Krishna's protection for the Pandavas . Lord Krishna consoles Kunti and promises to ever protect the Pandavas and guide them through troubles and problems that may occur in life . The sons of Pandu and Dhritarashtra progeny break into an argument . When Duryodhana insults the Pandavas as '' dependents '' , Bheema counters by saying that , the Kauravas are the progeny of a widow . Duryodhana asks Veda Vyasa for an explanation . He is then told that , since his mother , Gandhari had an astrological defect , she is first married of to a goat and then married to his father . Duryodhana gains animosity towards the kingdom of Gandhara where the king , the father of his mother Gandhari , rules . He attacks Gandhara and lays waste of the whole kingdom . He them imprisons the royal family in his prison . He gives them only one rice grain per prisoner . The king of Gandhara then stops everyone from grabbing the little food that is provided . He says that instead of everyone dying , they could keep at least one of their princes alive . He chooses Sakuni to be alive . Sakuni takes an oath that he will do everything he can to destroy the entire Kaurava clan . He makes magic dice from his father's spinal cord . The magic dice show exactly the number that he would want . Duryodhana takes pity on the lone prisoner , Sakuni after the rest of the Gandhara royal family dies in prison out of starvation . Sakuni joins the evil of coterie of Duryodhana , Karna and Dushyasana .
Do you have any questions?
MY QUESTION: Who makes dice from his father's spinal cord, and do they roll the right number?

QUES: Take a look at this train in Figure 1.11. It looks very futuristic. What do you notice about it? Did you notice that the train has no wheels? How can a train have no wheels? It doesn't need wheels. It actually floats, or levitates, just above the track. Magnets enable the train to do this. This is not a normal train. This is a maglev train. The word maglev stands for magnetic levitation. Because it has no wheels, there is no friction. Some magnets hold the train up. Other magnets are used to move the train forward. This train can go very fast. It can reach speeds up to 480 kilometers (300 miles) per hour! Magnets are pretty cool. What exactly is a magnet? How is it able to exert such force?
Do you have any questions?
MY QUESTION: How does the train move?

QUES: The highest point of a wave is the crest. The lowest point is the trough. The vertical distance between a crest and a trough is the height of the wave. Wave height is also called amplitude. The horizontal distance between two crests is the wavelength. Both amplitude and wavelength are measures of wave size. The size of an ocean wave depends on how fast, over how great a distance, and how long the wind blows. The greater each of these factors is, the bigger a wave will be. Some of the biggest waves occur with hurricanes. A hurricane is a storm that forms over the ocean. Its winds may blow more than 150 miles per hour! The winds also travel over long distances and may last for many days.
Do you have any questions?
MY QUESTION:
What are the highest and lowest points of a wave?