"Speed" is the rate at which distance is being covered .... the ratio
of distance covered to the time it takes.
"Velocity" is the rate at which distance is being covered .... the ratio
of distance covered to the time it takes ... AND the direction in which
it is covered. 'Speed' with the direction of the motion.
I posted this because I got it correct. The answer is 28J.
Answer:
Velocity v= 12.25 
Explanation:
The first rock dropped give the distance Y in meters

Now the motion of the second rock the time change so to know the velocity

Answer:
The maximum torque is
Explanation:
From the question we are told that
The length of the wire is 
The current flowing through the wire is 
The magnetic field is 
The maximum torque is mathematically evaluated as
Where
is the magnetic dipole moment which is mathematically represented as

Where
is the number of turns which from the question is 1
substituting values


Now