Consider two stars in orbit about a mutual center of mass. If a1 is the semimajor axis of the orbit of star of mass m1 and a2 is the semimajor axis of the orbit of star of mass m2, prove that the semimajor axis of the orbit of the reduced mass is given by a

If a substance is in the gas phase, which of qualities of the gas will stay constant? a: volume b: mass c: shape d: position of particles

Along the line connecting the two charges, at what distance from the charge q1 is the total electric field from the two charges zero? express your answer in terms of some or all of the variables s, q1, q2 and k =14ï€ïµ0. if your answer is difficult to enter, consider simplifying it, as it can be made relatively simple with some work.

Consider a u-tube whose arms are open to the atmosphere. now equal volumes of water and light oil (ρ = 49.3 lbm/ft3) are poured from different arms. a person blows from the oil side of the u-tube until the contact surface of the two fluids moves to the bottom of the u-tube, and therefore, the liquid levels in the two arms are the same. if the fluid height in each arm is 30 in, determine the gage pressure exerted by the person on the oil by blowing.