Amolecule of hydrogen moves at a speed of 115 cm/s. how long will it take to travel the length of a football field (100 yd long)?

You are driving to the grocery store at 20 m/s. you are 110m from an intersection when the traffic light turns red. assume that your reaction time is 0.50s and that your car brakes with constant acceleration. how far are you from the intersection when you begin to apply the brakes? what acceleration will bring you to rest right at the intersection? how long does it take you to stop after the light changes? the known values: vi=20m/s xi=110m t=.50s vf=0m/s xf=0m a=?

An object is placed in front of a concave mirror between the pole and the focus of the mirror, what is the nature of the image formed by the mirror

Acopper sheet has a volume of 100 cm³. if the density of copper is 8.9 g/cm³, what is the mass of the sheet? a. 11 g b. 8.9 g c. 189 g d. 890 g