Answer:
A=0.199
Explanation:
We are given that
Mass of spring=m=450 g=
Where 1 kg=1000 g
Frequency of oscillation=
Total energy of the oscillation=0.51 J
We have to find the amplitude of oscillations.
Energy of oscillator=
Where
=Angular frequency
A=Amplitude

Using the formula



Hence, the amplitude of oscillation=A=0.199
Answer:

Explanation:
Newton's 2nd Law relates the net force <em>F</em> on an object of mass <em>m </em>with the acceleration <em>a</em> it experiments by <em>F=ma.</em> In our case the net force is the friction force, since it's the only one the skier is experimenting horizontally and the vertical ones cancel out since he's not moving in that direction. Our acceleration then will be:

Also, acceleration is defined by the change of velocity
in a given time t, so we have:

Since we want the change in velocity, <em>mixing both equations</em> we conclude that:

Which for our values means:

Answer:
Newton's first law
Explanation:
it says that an object will continue to be at rest or keep moving till any external for is applied to it to make it move or stop respectively.
Answer:
When a car stops suddenly, the inertia the keeps you moving forward will finally stop and give you whiplash, which could seriously injure or even kill a baby. With the seat turned back, the force will be decreased dramatically, and prevent any fatal harm.