Atomic and Nuclear Physics Answers

As a sled moves across a flat snow-covered field at constant velocity, is any work done?

How does air resistance enter into the picture?

What is the coefficient of kinetic friction between the 100 N and 39 ⁰

How long will it take for a 10-mCi (370 MBq) sample of 32P(t1/2 ¼ 14.3 days) and a 100-mCi(3.7 GBq)sampleof67Ga(t1/2 ¼ 3.2 days) topossess the same activity?

A 60-kg patient about to have a brain scan is injected with 0.02 Ci of the radionuclide Technetium-99. Technetium-99 decays to the ground state with a half-life of 6.0 hours. The Technetium-99 nucleus decays by emitting a 143-keV photon. Assume that half of these photons escape the body without interacting. What biological equivalent dose does the patient receive? The relative biological effectiveness (RBE) for these photons is 0.97. Assume that all of the Technetium-99 decays while in the body

what is the magnitude of the electrostatic force between two electrons separated by a distance of 1.00 X 10-8 meter?

A train starts from a station nd travels with uniform acceleration 0.5ms for 20 second. it travels with uniform velocity for another 30 second , the brakes are then applied so that a uniform retardation is obtained and the train comes to rest in a further 10 second. Sketch the velocity time graph of this motion. Using ur graph, Calculate the total distance travelled by the train.

 The half-life of strontium-91, 91

38Sr is 9.70 h. Find 

(a) its decay constant, and

(b) for an initial 1.00-g sample, the activity after 15 hours. 

how does the distance at which an electron orbits the nucleus may be changed

A steel wire of length 0.8m and density 8x10³kgm-² is fixed at both ends when vibrating transversely under a tension of 50.0N. the fundamental frequency is 300Hz. Calculate the diameter of the wire in meters. How can the same wire be made produce a note for frequency 600Hz.