Recent content by ella_101

oH come on...someone knows the answer, or at least guide me! its bugging me not knowing.

An X-ray tube operating at 65kV has a tube current of 120mA. The tube produces X-ray with an efficiency of 0.8% calculate the rate of heat production in the anode rate = ? I really don't get this question, anyone?

In a motor vehicle, a relay is used to switch the 12 V , 60 W headlight on and off. The resistance of the relay coil is 150 ohms . Calculate the current in the relay coil when it is connected to a 12 V supply.

okay, x= ut + 1/2 at2 rearranged to give; u= 1/2at2 + x/t ( this is were I think I am going wrong , rearranging it?) than just plug in the numbers. = 65.5 OR alternatively you can 'show' your working out=)

I know its an 'easy' question but i think i am just getting the equation wrong

when i make 'u' the subject of the forumal i got 65.5 ( which is wrong) and for 'v' I got 121.5 I think my teacher said the answer was 9.5 for u and v i don't know, what did you get ?

Homework Statement A rocket powered sledge accelerates at 35ms-2 and takes 1.6s to pass through a 60m section of a test track. Find the speed at which it entered the section what was its speed when it left? Homework Equations I think this is the equation to use x=ut + 1/2at2 and...

“if a cyclist travels at an average speed of 3m/s-1 and turns home at an average speed of 9m/s than what is the average speed of the whole journey?” do I need an equation to work this out? And please show how you got your answer. Thanks