Answer:
A. when the mass has a displacement of zero
Explanation:
The velocity of a mass on a spring can be calculated by using the law of conservation of energy. In fact, the total energy of the mass-spring system is equal to the sum of the elastic potential energy (U) of the spring and the kinetic energy (K) of the mass:

where
k is the spring constant
x is the displacement of the mass with respect to the equilibrium position of the spring
m is the mass
v is the velocity of the mass
Since the total energy E must remain constant, we can notice the following:
- When the displacement is zero (x=0), the velocity must be maximum, because U=0 so K is maximum
- When the displacement is maximum, the velocity must be minimum (zero), because U is maximum and K=0
Based on these observations, we can conclude that the velocity of the mass is at its maximum value when the displacement is zero, so the correct option is A.
Answer: 10.36m/s
How? Just divide 200m by 19.3 and you will get how fast he ran per m/s
Answer:
a
Generally from third equation of motion we have that
![v^2 = u^2 + 2a[s_i - s_f]](https://tex.z-dn.net/?f=v%5E2%20%3D%20%20u%5E2%20%2B%202a%5Bs_i%20-%20s_f%5D%20)
Here v is the final speed of the car
u is the initial speed of the car which is zero
is the initial position of the car which is certain height H
is the final position of the car which is zero meters (i.e the ground)
a is the acceleration due to gravity which is g
So
=> 
b
Explanation:
Generally from third equation of motion we have that
![v^2 = u^2 + 2a[s_i - s_f]](https://tex.z-dn.net/?f=v%5E2%20%3D%20%20u%5E2%20%2B%202a%5Bs_i%20-%20s_f%5D%20)
Here v is the final speed of the car
u is the initial speed of the car which is zero
is the initial position of the car which is certain height H
is the final position of the car which is zero meters (i.e the ground)
a is the acceleration due to gravity which is g
So
=> 
When
we have that

=> 
=>
The mass of a planet determines the acceleration due to gravity on it. This is according to Newton's Law of Gravitation, which basically states that the more mass a body has, the greater the force of attraction it exerts on other bodies with mass near it.
The gravitational force is:
F = GMm/r², where G is a constant, r is the distance between large mass M and small mass m.
Considering the fact that acceleration is force per unit mass, if we divide gravitational force by the small mass (to get force per unit mass), we see the dependence mathematically:
a = GM/r²