I think it’s D...not sure tho !
The equation to be used is the derived formulas for rectilinear motion at a constant acceleration. The formula for acceleration is
a = (v - v₀)/t
where
v and v₀ are the initial and final velocities, respectively
t is the time
a is the acceleration
Since it started from rest, v₀ = 0. Using the formula:
0.15 m/s² = (v - 0)/[2 minutes*(60 s/1 min)]
Solving for v,
v = 18 m/s
Given that,
Mass of trackler, m₁ = 100 kg
Speed of trackler, u₁ = 2.6 m/s
Mass of halfback, m₂ = 92 kg
Speed of halfback, u₂ = -5 m/s (direction is opposite)
To find,
Mutual speed immediately after the collision.
Solution,
The momentum of the system remains conserved in this case. Let v is the mutual speed after the collision. Using conservation of momentum as :

So, the mutual speed immediately after the collision is 1.04 m/s but in opposite direction.
As stated in the statement, we will apply energy conservation to solve this problem.
From this concept we know that the kinetic energy gained is equivalent to the potential energy lost and vice versa. Mathematically said equilibrium can be expressed as


Where,
m = mass
= initial and final velocity
g = Gravity
h = height
As the mass is tHe same and the final height is zero we have that the expression is now:






Answer:
4. B and D
Explanation:
Two points along a transverse wave (such as the one in the figure) are said to be in phase when:
- the vertical position of the two points is the same
- The oscillation of the wave is going in the same way for both points
Basically, we say that two points are in phase when they are separated by a complete cycle (one complete oscillation) of the wave.
For this wave, we see that point B and C have same displacement, but they are not in phase since in B the oscillation is going down while in C is going up.
Instead, B and D are in phase, because they are separated by one complete cycle: both points have same displacement and the oscillation is going in the same way for both of them.