You and your housemate have an argument over the cost of the electric bill. You want to turn off the outside porch light before going to bed each night. Your housemate wishes to keep the light on from 6:00 PM each evening to 6:00 AM the next morning and says that this will not add any significant amount to the electric bill. If the porch light bulb is a 65 W bulb, how much will your housemate's plan contribute to the electric bill each month? Take the number of days in a month as 30 and the average cost of electricity is 17.0¢/kW · h.

Ablock of mass m = 2.5 kg is attached to a spring with spring constant k = 710 n/m. it is initially at rest on an inclined plane that is at an angle of θ = 23° with respect to the horizontal, and the coefficient of kinetic friction between the block and the plane is μk = 0.19. in the initial position, where the spring is compressed by a distance of d = 0.16 m, the mass is at its lowest position and the spring is compressed the maximum amount. take the initial gravitational energy of the block as zero. a) what is the block's initial mechanical energy? b) if the spring pushes the block up the incline, what distance, l, in meters will the block travel before coming to rest? the spring remains attached to both the block and the fixed wall throughout its motion.

Which statement is true? a. kepler's laws apply only to the motion of earth. b. kepler's laws can be used to predict eclipses. c. kepler's laws are true for a central force that is directly proportional to distance. d. kepler's laws can be deduced from newton's laws of motion and gravity.

Chameleons catch insects with their tongues, which they can rapidly extend to great lengths. in a typical strike, the chameleon's tongue accelerates at a remarkable 220 m/s2 for 20 ms, then travels at constant speed for another 30 ms.