Light of intensity 2.00 w/m2 passes through the pupil of one of your eyes and eventually falls on your retina. the radius of the pupil is controlled by the iris. in a human eye, the radius of the pupil can vary from about 1.0 mm to about 3.5 mm. the area of the opening can be calculated from pi (3.1416) times the radius squared. if your pupil is open to a radius of 3.5 mm, how much light energy passes through in one minute? give your answer in millijoules.

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.)

Simple machines can a. increase force only b. decrease force only c. increase or decrease force

Which of these is not a possible type of energy transformation? a. electrical energy into light energy b. sound energy into nuclear energy c. potential energy into kinetic energy d. kinetic energy into mechanical energy