Bắn đồng thời một proton và một electron vào từ trường đều theo phương vuông góc với các đường sức từ với cùng một vận tốc đầu. Khi proton quay được 1 vòng thì electron quay được bao nhiêu vòng? Cho mp = 1,67.10– 27 kg, me = 9,10.10 – 31kg.

Alow cost, low earth orbit (leo) satellite is to be fabricated at a university, for subsequent launch by rocket. what are the constraints and objectives for selection of a material suitable for the satellite bus (i.e. the structure)? explain each in brief. (15 marks) b)suggest sources of data which could support the selection of materials for applications in space. (5 marks) c) set weights for the objectives listed in (2a) using the digital logic method. (5 marks)

In which of the following cases is work being done on an object? question 2 options: pushing against a locked door carrying a box down a corridor pulling a trailer up a hill suspending a heavy weight with a strong chain

Red light strikes a metal surface and electrons are ejected. if violet light is now used with a 10% greater intensity, what will happen to the ejection rate (number of ejected electrons per second) and the maximum energy of the electrons? a) greater ejection rate; same maximum energyb) same ejection rate; greater maximum energyc) greater ejection rate; greater maximum energyd) same ejection rate; same maximum energye) none of the above answers are correct