A car with a mass of 1. 2 Ă— 103 kilograms starts from rest and attains a speed of 20 meters/second in 5 seconds. What net force acted on the car to cause that acceleration? A. 3. 0 Ă— 102 newtons B. 6. 0 Ă— 102 newtons C. 1. 2 Ă— 103 newtons D. 4. 8 Ă— 103 newtons E. 1. 2 Ă— 104 newtons.

Ascientist notices that an oil slick floating on water when viewed from above has many different colors reflecting off the surface, making it look rainbow-like (an effect known as iridescence). she aims a spectrometer at a particular spot and measures the wavelength to be 750 nm (in air). the index of refraction of water is 1.3

Amerry-go-round of radius r, shown in the figure, is rotating at constant angular speed. the friction in its bearings is so small that it can be ignored. a sandbag of mass m is dropped onto the merry-go-round, at a position designated by r. the sandbag does not slip or roll upon contact with the merry-go-round. how would you rank the following different combinations of m and r on the basis of the angular speed of the merry-go-round after the sandbag "sticks" to the merry-go-round from largest to smallest. a) m = 10kg, r = 0.25r b) m = 20kg, r = 0.25r c) m = 10kg, r = 0.50r d) m = 10kg, r = 1.0r e) m = 15kg, r = 0.75r f) m = 40kg, r = 0.25r

Acharged particle moves in a circular path in a uniform magnetic field. which of the following would increase the period of the particle's motion? check all that apply. increasing its chargeincreasing its massincreasing the field strengthincreasing its speed