Textbkpg35

__**Text book page 35 #4, 6, 7**__ (4) If a huge bear were chasing you, its enormous mass would be very threatening. But if you ran in a zigzag pattern, the bear's mass would be to your advantage. Why? Ans: Since the bear has enormous mass, it's not easy for it to change to different directions during motion.

(6) Consider a ball at rest in the middle of a toy wagon. When the wagon is pulled forward, the ball rolls against the back of the wagon. Interpret this observation in terms of Newton's first law. Ans: According to The Law of Inertia, the ball still remains in its original position when the toy wagon is pulled forward, so effectively the ball rolls to the back of the wagon because of the relative motion between them.

(7) Why do you lurch forward in a bus that suddenly slows? Why do you lurch backward when it picks up speed? What law applies here? When you are in the running bus, you have the same speed as the bus. So when the bus slows down, you have a relatively higher speed than the bus, therefore you will lurch forward. Conversely, when the bus picks up speed, the bus will have a higher speed than you, so you will lurch backward because of the relative motion.The concept of Inertia is applied here.