Answer:
122.5 N/m
Explanation:
According to the law of conservation of energy, if there is no air resistance or frictional forces, the initial elastic potential energy of the spring toy is entirely converted into gravitational potential energy when the toy reaches the highest point.
Therefore, we can write:

where the term on the left is the initial elastic potential energy while the term on the right is the gravitational potential energy, and where
k is the spring constant
x = 0.02 m is the compression of the spring
m = 0.01 kg is the mass of the toy
h = 0.25 m is the height reached by the toy
is the acceleration due to gravity
Solving for k,

Work = force x distance
= 100N (force) x 0.5m (distance)
= 50J
Answer:
the change in momentum = Force x change in time
Complete Question:
Which process is not required for an animal to obtain energy from food?
a. Secretion.
b. Digestion.
c. Excretion.
d. Ingestion.
Answer:
c. Excretion.
Explanation:
Excretion is a metabolic process in which living organisms gets their system rid of metabolic waste, water and excess ions. This is usually done with the aid of kidney, skin and lungs in all vertebrates.
Example of excretions are urination, sweating and defecation.