The mass of an electron is 9.11 x 10"kg. The mass of a proton is 1.67 x 10 kg. They are about 1.0 x 100 m apart in a hydrogen atom. What is the gravitational force between these two particles in the hydrogen atom?
GUESS A+

You notice a very one-dimensional-thinking snail crawling along one rail of a railroad track. naturally, you remove it to a safer place. but before you do, you observe it as it moves from position xi = -92.9 cm to position xf = -64.9 cm along the rail, as measured from a point where one rail abuts the next. what is the snail\'s displacement δx in centimeters?

An engineer designs a roller coaster so that a car travels horizontally for 152 ft, then climbs 137 ft at an angle of 34.0° above the horizontal. it then moves 137 ft at an angle of 48.0° below the horizontal. if we take the initial horizontal motion of the car to be along the +x-axis, what is the car's displacement? (give the magnitude of your answer, in ft, to at least four significant figures and give the direction of your answer in degrees counterclockwise from the +x-axis.)

Glass has a hardness that is in the middle of the hardness scale. what is the hardness of glass?