Answer:

Explanation:
The elastic potential energy of a spring is given by
, where
is the spring constant of the spring and
is displacement from point of equilibrium.
When released, this potential energy will be converted into kinetic energy. Kinetic energy is given by
, where
is the mass of the object and
is the object's velocity.
Thus, we have:

Substituting given values, we get:

Answer:
a)
b)
Explanation:
Given:
mass of bullet, 
compression of the spring, 
force required for the given compression, 
(a)
We know

where:
a= acceleration


we have:
initial velocity,
Using the eq. of motion:

where:
v= final velocity after the separation of spring with the bullet.


(b)
Now, in vertical direction we take the above velocity as the initial velocity "u"
so,

∵At maximum height the final velocity will be zero

Using the equation of motion:

where:
h= height
g= acceleration due to gravity


is the height from the release position of the spring.
So, the height from the latched position be:



We have F = kx or ma = kx where m and k are constants. Therefore, if x is halved, a must be halved too.
Answer:
2250N
Explanation:
W= mg,
where W= weight
m= mass
g= acceleration due to gravity
Given that the body is 90kg, m= 90kg.
Acceleration due to gravity of planet
= 2.5(10)
= 25 m/s²
Weight of body on planet
= 90(25)
= 2250N
*Mass is the amount of matter an object has and is constant (same on earth and the planet).