Answer:
Explanation:
The current from the battery always flows from the positive terminal of the battery to the negative terminal of the battery.
If we connect a red coloured wire to the positive terminal of the battery and black coloured wire to the negative terminal of the battery, and then reverses the wire to their respective terminals, then there is no change in the direction of flow of current. It does not matter that which wire is connected to the particular terminal. The current always flow from positive to negative terminal of the battery outside the battery.
Nothing will happen to the magnetic field.
BUT If you're talking about the magnetic force , then when changing the current direction , the direction of the magnetic force will be reversed.
(You'ld like to know :
-Changing direction of current ONLY , reverses the direction of magnetic force.
-Changing direction of Magnetic field only (poles of magnet) , reverses the direction of magnetic force.
-Changing the direction of both , magnetic field and current , doesn't effect direction of magnetic force.)
N.B : Magnetic Force is experienced only when direction of current is PARALLEL to direction of magnetic field .
--> Flemming Left Hand Rule is used to know direction of magnetic force.
Hope This Helps.
Answer : The half-life of this substance will be, 45 minutes.
Explanation :
First we have to calculate the value of rate constant.
Expression for rate law for first order kinetics is given by:
where,
k = rate constant = ?
t = time passed by the sample = 90.3 min
a = initial amount of the reactant = 400
a - x = amount left after decay process = 100
Now put all the given values in above equation, we get
Now we have to calculate the half-life of substance, we use the formula :
Therefore, the half-life of this substance will be, 45 minutes.
KE = 1/2 mv^2 is the relationship betwee mass and kinetic energy
I think the answer is B because I did this before
