Answer:
Explanation:
Given:
- mass of the object,
- elastic constant of the connected spring,
- coefficient of static friction between the object and the surface,
(a)
Let x be the maximum distance of stretch without moving the mass.
<em>The spring can be stretched up to the limiting frictional force 'f' till the body is stationary.</em>
where:
N = m.g = the normal reaction force acting on the body under steady state.
(b)
Now, according to the question:
- Amplitude of oscillation,
- coefficient of kinetic friction between the object and the surface,
Let d be the total distance the object travels before stopping.
<em>Now, the energy stored in the spring due to vibration of amplitude:</em>
<u><em>This energy will be equal to the work done by the kinetic friction to stop it.</em></u>
<em>is the total distance does it travel before stopping.</em>
According to Newton;s Second Law of motion, F = ma. Acceleration is the change of velocity per unit time. Since there is no change of velocity, then acceleration is equal to zero. Consequently, the net force F is also equal to zero. The net force is equal to the sum of all the forces acting on the body. These forces are the horizontal force and the frictional force. They are acting in opposite directions. So, the sum must be
F = 0 = Horizontal - Frictional
0 = 100 N - Frictional
Frictional force = 100 N
Answer:
The second ball
Explanation:
Both balls are under the effect of gravity, accelerating with exactly the same value. The first ball is dropped, therefore its initial velocity is zero. Since the second ball has horizontal and vertical velocity components, its initial velocity is given by:
The vertical component is zero, however, it has a horizontal velocity, so its initial speed is not zero, therefore the secong ball has the greater speed at ground level.