Awashing machine sits on the floor. how can you increase the force of friction on the washing machine without changing the surfaces of the floor or washing machine? explain your reasoning

If a clock aboard a space ship traveling at 0.900 c of the speed of light relative to earth chimes once at the beginning of the hour and again when it reads one hour later, how much time would an observer on earth say elapsed between the two chimes?

How would doubling the made of an object change the objects potential energy

The volume of a gas is halved during an adiabatic compression that increases the pressure by a factor of 2.5. what is the specific heat ratio? show the math steps .