In the simple bohr model of the eighth excited state of the hydrogen atom, the electron travels in a circular orbit around a fixed proton. the radius of the orbit is 4.28 ✕ 10−9 m, and the speed of the electron is 2.43 ✕ 105 m/s. the mass of an electron is 9.11 ✕ 10−31 kg. what is the force on the electron (in n)? (enter the magnitude.)

Decreased sensitivity to an unchanging stimulus is known as

An astronaut in space cannot use a scale or balance to weigh objects because there is no gravity. but she does have devices to measure distance and time accurately. she knows her own mass is 77.4 kg , but she is unsure of the mass of a large gas canister in the airless rocket. when this canister is approaching her at 3.50 m/s , she pushes against it, which slows it down to 1.30 m/s (but does not reverse it) and gives her a speed of 2.60 m/s . what is the mass of the canister?

Beryl states that insulation with the smallest possible thermal conductivity is best to keep a house warm in winter, but worst for keeping a house cool in summer. sapphire insists the reverse is true: low thermal conductivity is good in the summer, but bad in the winter. which one, if either is correct? a. beryl, because low thermal conductivity results in low heat transfer. b. beryl, because low thermal conductivity results in high heat transfer. d. sapphire, because low thermal conductivity results in high heat transfer. e. neither, because low heat transfer is desirable both in summer and in winter.