A laser emits photons continuously at a rate of 3.8*1016/s. If the wavelength of the photons is 541 nm, what is the laser power in mW

Apackage of supplies is dropped from a plane, and one second later a second package is dropped. neglecting air resistance, the relative velocity of the 1st package viewed from the second will 56) a) increase. b) be constant. c) be zero. d) depend upon their weight. e) decrease

An object weighs 40n in air, weighs 20n when submerged in water and 30n when submerged in a liquid of unknown density. what is the density of the liquid?

It's a snowy day and you're pulling a friend along a level road on a sled. you've both been taking physics, so she asks what you think the coefficient of friction between the sled and the snow is. you've been walking at a steady 1.5m/s, and the rope pulls up on the sled at a 32 ∘ angle. you estimate that the mass of the sled, with your friend on it, is 65 kg and that you're pulling with a force of 80 n .