An observer on earth measures the length of a spacecraft travelling at a speed of 0.700c to be 78.0 m long. determine the proper length of the spacecraft.

Moon effect. some people believe that the moon controls their activities. if the moon moves from being directly on the opposite side of earth from you to being directly overhead, by what percentage does (a) the moon's gravitational pull on you increase and (b) your weight (as measured on a scale) decrease? assume that the earth–moon (center-to-center) distance is 3.82 × 10^8 m, earth's radius is 6.37 × 10^6 m, moon's mass is 7.36 × 10^22 kg, and earth's mass is 5.98 × 10^24 kg.

2. -/1 pointsserpse10 2.7.p.017.mi. an object moving with uniform acceleration has a velocity of 14.0 cm/s in the positive x direction when its x coordinate is 2.97 cm. if its x coordinate 2.85 s later is -5.00 cm, what is its acceleration? cm/s2 need ? read it master it

Electromagnetic induction. a coil of wire contains n turns and has an electrical resistance r. the radius of each turn is a. initially, inside the coil there exists a uniform magnetic field of magnitude b0 parallel to the axis of the coil. the magnetic field is then reduced slowly. the current induced in the coil is i. how long does it take for the magnitude of the uniform field to drop to zero?