Explanation:
It is given that,
Mass of an object, 
(a) Time period of oscillation, T = 2.4 s
The formula for the time period of spring is given by :

Where
k is the force constant



(b) Displacement in the spring, x = 2.2 m
Energy stored in the spring is given by :



Hence, this is the required solution.
Answer:
b) Springs oscillate with the same frequency,
Explanation:
expression for frequency of vibration of mass hanging from a spring is given as follows
f = 
k is force constant of spring and m is mass vibrating .
In the present case, if mass stretches the spring by x and remains balanced
mg = k x

g and x are same for both cases
will also be same for both cases .
Hence frequency of vibration will also be same for both the balls .
To solve this problem we will apply the given concept for torque which explains the relationship between the force applied and the distance to a given point. Mathematically this relationship is given as

Where,
Torque
F = Force
d = Distance
Our values are given as,

Therefore replacing we have that the force is

F = 12.72N
Therefore the least amount of force that you must exert is 12.72N
Answer:
First answer.
Explanation:
There may be a 5N force, but if the frictional force also equals 5N, than they cancel eachother out, resulting in the brick still staying still, as it is resting on a (perfectly) level surface, but any amount of force would make the brick move.
<span>Newton's law of universal gravitation is an INVERSE SQUARE LAW, which rules out C and D.It is proportional to the masses involved, which rules out B.A could be seen as one form of the lawF=G m1 m1/r^2Though I recognise it more as F=G m1 m2/r^2.G is the universal gravity constant and is distinct from g which is the acceleration of gravity LOCAL to a planet or moon. So, g is LOCAL, G is universal.Newton was a smart bloke, as are all these scientists whose names frequently appear.
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