To solve this problem it is necessary to apply the concepts related to the frequency in a spring, the conservation of energy and the total mechanical energy in the body (kinetic or potential as the case may be)
PART A) By definition the frequency in a spring is given by the equation

Where,
m = mass
k = spring constant
Our values are,
k=1700N/m
m=5.3 kg
Replacing,


PART B) To solve this section it is necessary to apply the concepts related to the conservation of energy both potential (simple harmonic) and kinetic in the spring.

Where,
k = Spring constant
m = mass
y = Vertical compression
v = Velocity
This expression is equivalent to,

Our values are given as,
k=1700 N/m
V=1.70 m/s
y=0.045m
m=5.3 kg
Replacing we have,

Solving for A,



PART C) Finally, the total mechanical energy is given by the equation



Answer:
19.6m/s
Explanation:
A Rock falling off a cliff can be modeled as an object starting with zero velocity moves with constant acceleration for certain period of time, for such motion following equation of motion can be used.
here in our case
because object starts off from rest and
is acceleration because of gravity ( Motion under gravity).
and of course t = 2 second.
Now by substituting all this information in equation of motion we get.

that would be the velocity of rock as it would hit the ground.
Note! We have assumed that there is no air resistance.
A rock falling off a cliff can be modeled as an object starting with zero velocity moves with constant acceleration for a certain period of time, for such motion following equation of motion can be used.
here in our case because object starts off from rest and is acceleration because of gravity ( Motion under gravity).
and of course t = 2 seconds.
Now by substituting all this information in equation of motion we get.
V = 19.6m/s
that would be the velocity of rock as it would hit the ground.
Note! We have assumed that there is no air resistance.
Answer:
Energy stored, U = 66.6 J
Explanation:
It is given that,
Number of turns in the solenoid, n = 500
Radius of solenoid, r = 1.5 cm = 0.015 m
Distance, d = 15 cm = 0.15 m
Let U is the energy stored in the solenoid. Its formula is given by :

L is the self inductance of the solenoid

N is the no of turns per unit length


L = 0.00148 Henry

U = 66.6 J
Out of given options, the correct option for the energy stored in the solenoid is 70 J. So, the correct option is (a) "70 J".
C) The weight of the object on planet A will be less than the weight of the object on planet B.
This happened because: when gravitational pull of a planet is weak, an object will weigh less as a result of less gravity forcing it down to the ground.