Question

# 1. Usain Bolt sprints along the track, with his feet pushing down and behind him. Therefore...

1. Usain Bolt sprints along the track, with his feet pushing down and behind him. Therefore the track actually pushes Usain Bolt along the track. Group of answer choices True or False

2.You study two objects in motion, Object J and Object S. Each object has its own velocity graph, with same time and velocity scales. The slope of each graph is positive, upward and to the right  ⁄ but Object J's tilt angle is only 10º and Object S's tilt angle is quite steep, 85º. Which statement below is unquestionably correct?

Hint: make two careful sketches on your scratch paper.

Object J gains a smaller amount of speed per second than S.

Object S is moving to the right.

Object S is moving at higher speed than Object J.

Object J is moving to the left.

3. The y-coordinate equation for a free-fall trajectory,

exemplifies an essential part of what scientists want to do:

control the discussion of ideas.

predict the future state of a physical system.

elect Galileo or other professor to an informal political office, King of All Sciences.

construct a history of mathematical understanding.

4. As the first actions in a basic study of motion in two dimensions, a scientist must set up a coordinate system and decide on ________.

whether to follow Galileo or Aristotle

an appropriate distance scale, meters vs. light years vs. nanometers

the best strategy to use, mathematics vs. music vs. pure logic.

which came first, the chicken or the egg

5.An object with increasing acceleration, like the one we studied in lecture, does not in itelf, provide a true distance rectangle or distance triangle on its velocity graph. However, the area under the graph can be calculated, like in the film "Hidden Figures," by using

the principle of the tortoise and the hare, i.e., average speed.

circular or parabolic arcs, just as the famous Euler Method uses.

Euler's Method, which Katherine Johnson invented.

many narrow trapezoids made of a rectangle and a triangle.

6.We say that the changes in velocity of the two skateboarders are unequal in size when

their Δv vectors are equal in size and the same direction.

their masses are not the same.

Newton’s third law says their interaction forces are the same size.

the time formula, d = (1/2)gt2, is reversible.

7. The moon exerts a number of Newtons of gravitational force on Earth: F(moon →Earth)

The Earth exerts a number of Newtons of gravitational force on the moon: F(Earth →moon)

These two forces have the following relationship....

neither

both equal in size and opposite in direction

equal in size

opposite directions

8. Geosynchronous communication satellites orbit Earth every 24 hours, and they all orbit at the same altitude.

9.

You observe a coin at position x1 with velocity v1 = 1.6 m/sec away from you, moving toward point x2 on the x-axis, as shown.

The coin's mass is m = 0.005 kg.

There is a friction force of size f = 0.021 N that acts on it.

Calculate the stopping acceleration on the coin.

#### Earn Coins

Coins can be redeemed for fabulous gifts.