Answer:
its C. The north pole of one magnet attracts the south pole of another
Explanation:
I JUST TOOK THE TEST
Answer:
The average impact force is 12000 newtons.
Explanation:
By Impact Theorem we know that impact done by the sledge hammer on the chisel is equal to the change in the linear momentum of the former. The mathematical model that represents the situation is now described:
(1)
Where:
- Average impact force, in newtons.
- Duration of the impact, in seconds.
- Mass of the sledge hammer, in kilograms.
,
- Initial and final velocity, in meters per second.
If we know that
,
,
and
, then we estimate the average impact force is:


The average impact force is 12000 newtons.
The answer is C. friction, acting in opposition to the motion of the ball
Answer:
so rate constant is 4.00 x 10^-4 
Explanation:
Given data
first-order reactions
85% of a sample
changes to propene t = 79.0 min
to find out
rate constant
solution
we know that
first order reaction are
ln [A]/[A]0 = -kt
here [A]0 = 1 and (85%) = 0.85 has change to propene
so that [A] = 1 - 0.85 = 0.15.
that why
[A] / [A]0= 0.15 / 1
[A] / [A]0 = 0.15
here t = (79) × (60s/min) = 4740 s
so
k = - {ln[A]/[A]0} / t
k = -ln 0.15 / 4740
k = 4.00 x 10^-4 
so rate constant is 4.00 x 10^-4 