Activity 5: Check for Understanding (5 mins} Student Engagement (5E) Think-Pair-Share Solve the problem. 1. You are working at a radar station for the Coast Guard. While everyone else is out to lunch, you hear a distress call from a sinking ship. The ship is located at a distance of 51 .2 km from the station. at a bearing of 36\" west of north. On your radar screen you see the location of four other ships as follows: Ship Distance from Station {km} Bearing Maximum speed (krm'h) 1 36.1 42\" w of N 30.0 3?.3 61 \" w of N 38.0 2 3 10.2 36" W of N 32.0 4 51.2 7'9\" W of N 45.0 Quick! Which ship do you contact to help the sinking ship? Which ship will get there in the shortest time interval? Assume that each ship would accelerate quickly to its maximum speed and then maintain that constant speed in a straight line for the entire trip to the sinking ship. Activity 5: Check for Understanding {5 mins} Student Engagement (SE) Think-Pair-Share Solve the problem. 'I. Determine the resultant of the following: 81) N at 40\Activity 5: Check for Understanding (5 mins) Student Engagement (SE) Think-Pair-Share Solve the problem. 'I. You are working as a letter sorter in the Post Office. Postal regulations require that employees' footwear must have a minimum coefficient of static friction of {1.5 on a specied tile surface. You are wearing athletic shoes for which you do not know the coefficient of static friction. To determine the coefficient, you imagine that there is an emergency and start running across the room. You have a co-worker time you, and nd that you can begin at rest and move 4.23 m in 1.20 s. If you try to move faster than this, your feet slip. Assuming your acceleration is constant, does your footwear qualifyr for the postal regulation? Activity 5: Check for Understanding (5 mins) Student Engagement (SE) Think-Pair-Share Solve the problem. 1. You are working as a delivery person for a dairy store. In the back of your pick-up truck is a crate of eggs. The dairy company has run out of bungee cords, so the crate is not tied down. You have been told to drive carefully because the coefficient of static friction between the crate and the bed of the truck is 0.6. You are not worried, because you are traveling on a road that appears perfectly straight. Due to your confidence and inattention, your speed has crept upward to 45 miles per hour. Suddenly you see a curve ahead with a warning sign saying, "Danger: unbanked curve with radius of curvature 35 m". You are 15 m from the beginning of the curve. What can you do to save the eggs: (a) take the curve at 45 mifh, (b) brake to a stop before entering the curve to think about it, or it) slow down to take the curve at a slower speed? Discuss these options in your group and determine if there is a best course of action. Illictivityr 5: Check for Understanding {5 mins) Student Engagement (5E) Think-Pair-Share Solve the problem. 1. You are working as an expert witness for the defense of a container ship captain whose ship ran into a reef surrounding an island. The captain is being charged with intentionally running the ship into the reef. In discovery, the following information is correct: The ship was traveling at 2.5 ms toward the reef when a mechanical failure caused the rudder to jam in the straight-ahead position. At that point in time, the ship was 900 m from the reef. The wind was blowing directly toward the reefand exerting a constant force of 9.00 X103 N on the boat in a direction toward the reef. The mass of the ship and its cargo was 5.50 x 10? kg. During the preparation for the trial, the captain claims that without control of the direction of travel, the only choice he had was to put the engines in reverse at maximum power, such that the total force exerted by the frictional drag force of the water on the propeller was 1.25 x 105 N in a direction away from the reef. From this information, construct a convincing argument that nothing the captain could do in this situation could have prevented the ship from striking the reef. Activity 5: Check for Understanding (5 mins) Student Engagement (SE) Effective Questioning How does the ideal mechanical advantage (IMA) of an inclined plane vary with the angle 0 of the plane; that is, what trigonometric function of 0 gives the value of IMA?Student Engagement (SE) Think-Pair-Share Solve the problem. 1. You are using a wheel and axle as a simple machine. You applied a force of 30 lb to the rim of the wheel so that it can lift a load of 240 lb. The diameters of the wheel and axle are 3 feet and 4 inches, respectively. Determine the efficiency of the machine.Activity 5: Check for Understanding (5 mins) Student Engagement (SE) Effective Questioning Which would be more effective, a hammer that collides elastically with a nail, or one that collides perfectly inelastically? Assume that the mass of the hammer is much larger than that of the nail.Activity 5: Check for Understanding (5 mins) Student Engagement (SE) Effective Questioning Describe how you can use a simple experiment involving moment of inertia to 00090000800 determine whether an egg is raw or hard- boiled.' -=-- Check for Understanding {5 mins) Student Engagement (5E) Effective Questioning . What is the purpose of the steel in a horizontal reinforced concrete beam? In a vertical column? Does concrete need reinforcement more under compressive or more under tensile stresses? Why? 4} Activity 5: Check for Understanding (5 mins) Student Engagement (SE) Effective Questioning (v A body is immersed in a liquid in such a way that it is closely in contact with the bottom and there is no liquid beneath the body. Is there a buoyant force on the body? Explain. ((Xou attach an object to the bottom end of a hanging vertical spring. It hangs at rest after extending the spring 18.3 cm. You then set the object vibrating. Do you have enough information to find its period? Explain your answer and state whatever you can about its period. 4} Activity 5: Check for Understanding {5 mine) Student Engagement (SE) Effective Questioning Show that the equation or = J; doea give the appropriate units for velocity. 4) Activity 5: Check for Understanding (5 mins) Student Engagement (SE) Effective Questioning Why is a water tower generally placed on top of a hill? if the hill is 50 m high, can it supply water to the top floor of a 100-m tall office building? If not, how does water get to that floor?Activity 5: Check for Understanding (5 mins) Student Engagement (SE) Effective Questioning Two strings A and B are given. The length of A is twice that of B. The total mass of A is one-third that of B. If the tension in wire A is one-half that of B and the fundamental frequency of A is 400 Hz, what is the fundamental frequency of string B?Activity 5: Check fer Understanding (5 mine] Student Engagement {SE} Effective Questioning Hew dd you account fer the fact that solids and liquids generallyr expand when heated? Activity 5: Check for Understanding (5 mins) Student Engagement (SE) Effective Questioning Your cup of hot coffee has been poured, but you are still doing some work on your computer before you take a sip. You intend to add some milk to your coffee. To keep the coffee hot as long as possible, should you add the milk at once, or wait until just before you take the first sip