One airplane travels due north at 300 km/h while another travels due south at 300 km/h. are their speeds the same?

How much force must a locomotive exert on a 12840-kg boxcar to make it accelerate forward at 0.490 m/s2?

If you held a stone over the mouth of a well and then let it go , what would happen to the stone? explain your answer.

The lid of a pressure cooker forms a nearly airtight seal. steam builds up pressure and increases temperature within the pressure cooker so that food cooks faster than it does in an ordinary pot. the system is defined as the pressure cooker and the water and steam within it. if 2.0 g of water is sealed in a pressure cooker and then vaporized by heating, and 5127 j must be added as heat to completely vaporize the water, what is the change in the system’s internal energy? answer in units of j.