Suppose that the resistive force of the air on a skydiver can be approximated by f = -bv2. If the terminal velocity of a 50.0-kg skydiver is 60.0 m/s, what is the value of b? 0.46 kg/m 0.28 kg/m 0.14 kg/m 0.98 kg/m
Image text
Suppose that the resistive force of the air on a skydiver can be approximated by . If the terminal velocity of a skydiver is , what is the value of ?
![A penguin of 7 kg stands at the edge of an ice cliff and dives into the ocean below. The penguin has an initial velocity of 5 ms−1 and at an angle of 60∘ with respect to the horizontal. The cliff is 15 m above the water level. Assume air resistance is negligible and take the value of the acceleration due to gravity as 9.81 ms−1. Calculate: a) The time it takes for the penguin to hit the water. [3 marks] b) The horizontal distance travelled by the penguin before hitting the water. [2 marks] c) The velocity of the penguin just before hitting the water. [3 marks] d) The momentum of the penguin in unit vector notation at the highest point (with respect to the water level) of its projectile. [2 marks] e) Supposed that upon splashing on the water, the magnitude of the vertical component of the velocity found in part (c) above is being reduced by half in 0.2 seconds while the horizontal component remained the same, determine the impulsive force experience by the penguin. [2 marks].](https://www.doubtrix.com/uploads/editor/7669666301lraWjZPvzV.jpg)
![Definite integrals are useful to science because we can often describe natural phenomena using definite integrals. However, integrating functions arising in real-life science can be rather challenging. In this exercise, we see how having only the graph of some functions is enough to answer some questions in science. The physical interpretation of an integral is a prerequisite knowledge you learned in MATH 1013. For a refresher, see the Net Change Theorem in Section 5.4 of the textbook. A group of researchers studies the population of arctic foxes in Northern Canada. Initially, the researchers identified a population of 1,000 arctic foxes. Due to various factors, the population of arctic foxes changes over time. The graph of the birthrate B(t) and the death rate D(t), for the population, are shown below. Time t is measured in years. (1) In a sentence or two, describe the meaning of the function f(t) = t 0 B(x) - D(x)dx in the context of this problem. (2) According the graph, is there a time t between 0 and 20 at which the population is equal to the initial population? If so, provide a rough estimate of this time, and write one or two sentences explaining how you found it. Your estimate should be a single number, not an interval. (3) Recall from Quiz 1 the definition of the average value of a function f(x). The average value of a function f(x) over an interval [a, b] is denoted by favg and is defined to be favg = 1 b - a b a f(x)dx. Suppose you know that the average birth rate over the first 20 years is 90 arctic foxes per year and the average death rate over the first 20 years is 100 arctic foxes per year. What is the population of the arctic foxes at t = 20 ? Show your work.](https://www.doubtrix.com/uploads/editor/1288831183fhExDQGbmw.png)
