-17.555m/s
first I found the time it took for jacks stone to reach the bottom, using the formula vf = vi + at, vf and vi are final and initial velocities.
then i found the velocity at 6.6m using vf^2 = vi^2 + 2ad
and I found the time it took to get to 6.6m, so that I knew how long Jill waited to throw her stone, I used the formula d = t(vi+vf)/2, then i done total time - the time she waited, to get the time it took for there stones to hit the ground at the same time.
then to find the initial velocity of her throw I used the formula d = vit + (at^2)/2
Answer:
Mg and HCl
Explanation:
Here, we want to get the combination that could be used in the production of the needed hydrogen
An important chemical property of inorganic acids is that when they react with metals, they give off hydrogen gas in conjunction with the formation of a salt
HCl is a mineral acid while Mg is a metallic substance
So the reaction between this metal and the mineral acids will give the needed hydrogen gas to be produced
The acceleration of the car at impact is 15m/s².
<h3>What is Newton's Second Law of Motion?</h3>
Newton's second law provides a precise explanation of the modifications that a force can make to a body's motion. According to this, a body's momentum changes at a rate that is equal to the force acting on it over time in both magnitude and direction. A body's momentum is equal to the sum of its mass and velocity. Similar to velocity, momentum has both a magnitude and a direction, making it a vector quantity.
acceleration - rate of change of velocity with time, both in terms of speed and direction. A point or object going straight forward is accelerated when it accelerates or decelerates.
There are three types of accelerated motions :
- uniform acceleration,
- non-uniform acceleration
- average acceleration.
express all the units in their most basic form.
kg, newton = kg*m/s², acceleration =m/s²

to learn more about Newton's Second law of Motion - brainly.com/question/13447525
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