0.2 Dynamics (Forces and Newton's Laws)

Last updated 3 months ago

5 questions

Required

0.2 Dynamics (Forces and Newton's Laws)

Last updated 3 months ago

5 questions

Our textbook for this summer assignment will be OpenStax College Physics for AP Courses. Please study sections 4.1-4.6 in the book, and then do Problems 4, 9, and 16 in the "Problems and Exercises" section for Chapter 4. Put your answers below. If you format your answers correctly, formative will auto-grade when you submit the assignment. Include units on all answers, with a space before the unit. For instance, "27.4 km/s". Express large and small numbers in scientific notation with the letter e: "4.5e13 kg".

Required

4. Since astronauts in orbit are apparently weightless, a clever method of measuring their masses is needed to monitor their mass gains or losses to adjust diets. One way to do this is to exert a known force on an astronaut and measure the acceleration produced. Suppose a net external force of 50.0 N is exerted and the astronaut’s acceleration is measured to be 0.893 m/s2
(a) Calculate her mass to one decimal place.

Required

4. Since astronauts in orbit are apparently weightless, a clever method of measuring their masses is needed to monitor their mass gains or losses to adjust diets. One way to do this is to exert a known force on an astronaut and measure the acceleration produced. Suppose a net external force of 50.0 N is exerted and the astronaut’s acceleration is measured to be 0.893 m/s2
(b) By exerting a force on the astronaut, the vehicle in which they orbit experiences an equal and opposite force. Discuss how this would affect the measurement of the astronaut’s acceleration. Propose a method in which recoil of the vehicle is avoided.

Required

9.
Suppose two children push horizontally, but in exactly opposite directions, on a third child in a wagon. The first child exerts a force of 75.0 N, the second a force of 90.0 N, friction is 12.0 N, and the mass of the third child plus wagon is 23.0 kg. Calculate the acceleration to three decimal places.

Required

16.
A brave but inadequate rugby player is being pushed backward by an opposing player who is exerting a force of 800 N on him. The mass of the losing player plus equipment is 90.0 kg, and he is accelerating at 1.20m/s2 backward. (a) What is the force of friction between the losing player’s feet and the grass?

Required

16.
A brave but inadequate rugby player is being pushed backward by an opposing player who is exerting a force of 800 N on him. The mass of the losing player plus equipment is 90.0 kg, and he is accelerating at 1.20m/s2 backward. (b) What force does the winning player exert on the ground to move forward if his mass plus equipment is 110 kg?