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If an object is moving eastward and slowing down, then the direction of its acceleration vector is ____.

The two measurements necessary for calculating average speed are:

If a rocket initially at rest accelerates at a rate of 50 m/s2 for one minute, its speed will be

A car with an initial velocity of 5.0 m/s experiences a constant acceleration of 2.0 m/s2.  What is the car’s displacement during the first 6.0 s of its motion?

A bullet shot horizontally from a gun:

Sara has lived 18.0 years. How many seconds has she lived? Express the answer in scientific notation. Use 365.24 days per year for your calculations.

An object is shot vertically upward. While it is rising:

  The kinetic energy of an object is given by the equation KE = (1/2)mv2, where m is mass and v is speed, with dimensions L/T. What are the dimensions of KE? ML2/T2 L2/T2 LM/T  

There are many estimates of the number of stars in the universe. One estimate is that there are 1010 stars in the Milky Way galaxy, and that there are 1010 galaxies in the universe. Assuming that the number of stars in the Milky Way is the average number of stars in a galaxy, estimate how many stars there are in the universe. It perhaps goes without saying: Express your answer in scientific notation.

Mercury orbits the Sun at a mean distance of 57,900,000 kilometers. (a) What is this distance in meters? Use scientific notation to express your answer and state it with three significant figures.