Tính công suất động cơ phát ra

Which type of electromagnetic waves are dangerous enough to be used to kill cancerous cells? (a)gamma rays (b)visible light (c)infrared light (d)microwaves

The charge on a charged sphere is: a)concentrated at its centerb)distributed uniformly throughout its volumec)clustered on its centerd)distributed uniformly over its surface

An object dropped from cliff falls with a constant acceleration of 10 metre per second square find its speed of two seconds after it was dropped