Part A)
As we know that spring force is given by
F = kx
here x = stretch in the spring from natural length
So here when spring reaches to its natural length
Force due to spring = 0
so acceleration = 0
Part b)
When spring is compressed from its natural length it will have elastic potential energy in it
so it is given by

now we know that there is no friction in it so maximum kinetic energy of the launcher must be equal to the elastic potential energy of the spring

here we have
k = 70 N/m
x = 0.4 m


Part c)
Now to find the speed we know that



so its speed is 6.11 m/s
1. Law of conservation of energy states that energy cannot be created, nor destroyed, for example, windmills take kinetic energy(movement energy) and convert it into electrical energy using gears and a generator as well as the blades.
so this supports it because the pendulum never reaches the same height twice unless you reset it so the energy is always getting less and less and not randomly getting back onto the pendulum.
2.Gravity, friction and air resistance slow it down as well
3. at the top, potential energy is the amount of energy something has relative to the amount it can disperse before stopping, for example, a book on a shelf has more potential energy than that of a book on a table, this is because when the shelf book falls it will create more energy than the table book.
Answer: True
Explanation: Following are the properties that are used to identify minerals:
(1) Color
(2) Hardness
(3) Magnetism : It is the property of mineral to attract or repel with other magnetic materials.
(4) Luster : It is the property that shows the surface is reflecting light or not.
(5) Reactivity: Reactivity is also responsible to identify mineral. How the mineral is reacting with acids, bases etc helps to identify type of minerals.
To solve this problem we will apply the concepts related to momentum and momentum on a body. Both are equivalent values but can be found through different expressions. The impulse is the product of the Force for time while the momentum is the product between the mass and the velocity. The result of these operations yields equivalent units.
PART A ) The Impulse can be calculcated as follows

Where,
F = Force
Change in time
Replacing,


PART B) At the same time the momentum follows the conservation of momentum where:
Initial momentum= Final momentum
And the change in momentum is equal to the Impulse, then

And

There is not initial momentum then



Explanation:
That's because the Sun's acceleration is much smaller