Agas of helium atoms (each of mass 6.65 × 10-27 kg) are at room temperature of 20.0°c. what is the de broglie wavelength of the helium atoms that are moving at the root-mean-square speed? (h = 6.626 × 10-34 j · s, the boltzmann constant is 1.38 × 10-23 j/k)

After the near spacecraft passed mathilde, on several occasions rocket propellant was expelled to adjust the spacecraft's momentum in order to follow a path that would approach the asteroid eros, the final destination for the mission. after getting close to eros, further small adjustments made the momentum just right to give a circular orbit of radius 45 km (45 × 10^3 m) around the asteroid. so much propellant had been used that the final mass of the spacecraft while in circular orbit around eros was only 545 kg. the spacecraft took 1.04 days to make one complete circular orbit around eros. calculate what the mass of eros must be.

Matter is needed to transfer thermal energy bya. conductionb. convectionc. radiation d. both a & b.

Why does the equilibrium position of the spring change when a mass is added to the spring? will the mass oscillate around the new equilibrium position of the spring or the previous position without a mass attached to the spring? if the equilibrium position of the spring changes by 20 cm (assuming no initial mass) when a mass is added to the spring with constant 4.9 kg/s^2, what is the mass of the object attached to the spring?