Exam (elaborations) PHY PHY 102

Complete the following exercises. Jane is collecting data for a ball rolling down a hill. She measures out a set of different distances and then proceeds to use a stopwatch to find the time it takes the ball to roll each distance. What is the independent variable in her experiment? The independent variable is represented by the ball. What is the dependent variable in her experiment? The Dependent variable is represented by the stopwatch. Give one control variable for her experiment. The control variable represents the distance. Consider an experiment where you drop an object. a. Briefly describe your proposed experiment. (Make sure it is controlled). I will drop a basketball off the second floor of my apartment building. b. What would be the independent variable for your experiment? The independent variable would be the basketball. c. What would be the dependent variable for your experiment? Would be the second floor distance of the drop. d. Give one control variable for your experiment. The Height of the drop. 2. Consider a freely falling object. a. What is the acceleration (in m/s2) after 5 seconds of fall? 9.8 m/s2 b. What is the acceleration (in m/s2) after 10 seconds of fall? 9.8 m/s2 c. What is the velocity (in m/s) after 5 seconds of fall?98m/s d. What is the velocity (in m/s) of 10 seconds of fall?98m/s 3. A sign is hung between two cables as illustrated below. If the sign weighs 350 N, what is the tension (in N) in each cable? T=mg/2=350/2=175N 4. A construction worker on a high-rise building is on a platform suspended between two cables as illustrated below. The construction worker weighs 850 N, the plank weighs 450 N, and the tension in the left cable is 550 N. a. What is the tension (in N) in the right cable? The tension in the right string will be = Weight of the worker + Weight of the Plank - Tension in the left string b. Explain your answer. 850 + 450 – 550=750N 5. Two forces of 50 N and 30 N, respectively, are acting on an object. Find the net force (in N) on the object if … a. the forces are a ..............................Continued......................