a bus moving at speed of 25m/s beginning to slow at rate 4m/s^2each second how long does it take to stop

Explanation:

Initial velocity is 25m/s i.e. u. Final velocity would be zero since the bus stopped. It is noted that the bus deccelartion of 4m/s, so the acceleration should be considered negative of 4m/s I.e. 4m/s. So using third law of motion i.e.

v^2 - u^2= 2as

(0)^2 - (25)^2= -2×4×s {Note here I used minus sign in acceleration}

-625 = -8×s

s=625 ÷ 8

s= 125 m

So bus would cover a distance of 125m before coming to rest.

the amount of current in the coil

because if the tool that you are using is not balanced it there would be false mass.