What is the correct reference frame for a given situation?

A car requires 1x10^8J of energy to drive 30km. calculate how many kilometers you could hypothetically drive using the energy contained in the rest mass of 100mg of fuel.

A jogger accelerates from rest to 3.0 m/s in 2.0 s. A car accelerates from 38.0 to 41.0 m/s also in 2.0 s. (a) Find the acceleration (magnitude only) of the jogger, (b) Determine the acceleration (magnitude only) of the car.

Two objects attract each other gravitationally. If the distance between their centers increases by a factor of 3, and both of the objects' masses increase by the same factor, how does the gravitational force between them change?

The Coelocanth is a very interesting, quite primitive fish thatlive deep in the ocean. Watching these beautiful creatures on anature documentary, you notice that they are able to stay basicallyat one position in the water with only slight movements

Which makes better packing material: a high density or a low density material why?

The velocity of a 200 kg object is changed from 5 m/s to 25 m/s in 50 seconds by an applied constant force. a. What change in momentum does the force produced? b. What is the magnitude of the force?

Is it 100% sur than electron have negative charg and proton have pasitive?

The periodic table contains many pieces of information. Which of the following pieces of information does each square contain?

Which will produce a bigger acceleration: a force of 10.0 N acting on a mass of 5.0 kg, or a force of 5.0 N acting on a mass of 10.0 kg?

In which of the following are action and reaction forces involved? A. when a tennis racket strikes a tennis ball B. when stepping from a curb C. when rowing a boat D. all of the above