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  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.

An object has a constant acceleration of 3 m/s2. The velocity versus time graph for this object has a slope:

The velocity-time graph of an object is a straight line with a positive slope. The object has:

The quantity with the same units as force times time, F t  , with dimensions MLT-1   is

A ball is thrown straight up with a speed of 36.0 m/s.  How long does it take to return to its starting point?

Calculate the following problem and express your answer with the correct number of significant digits: 123.09 – 1.7

The equation for the change of position of a train starting at x = 0  is given by  x = a t2 + b t3  The dimensions of b are

A PC microprocessor runs at 2.40 GHz. A hertz (Hz) is a unit meaning “one cycle per second.” A movie projector displays images at a rate of 24.0 Hz. What is the ratio of the microprocessor’s rate in cycles per second to the update rate of a movie projector? Answer the question using scientific notation.