Answer:

Explanation:
Let's use the conservation of momentum to solve it.
(1)
- The total initial momentum will be:

- The total final momentum will be:
, but as they stick together after the collision, v1f = v2f = vf.
So we can rewrite (1), using the above information:




Finally, the magnitude of the velocity of the wreckage of the two cars immediately after the collision is:

I hope it helps you!
Complete Question
The complete question is shown on the first uploaded image
Answer:
Explanation:
From the question we are told
The amplitude of the lateral force is 
The frequency is 
The mass of the bridge per unit length is 
The length of the central span is 
The oscillation amplitude of the section considered at the time considered is 
The time taken for the undriven oscillation to decay to
of its original value is t = 6T
Generally the mass of the section considered is mathematically represented as

=> 
=> 
Generally the oscillation amplitude of the section after a time period t is mathematically represented as

Here b is the damping constant and the
is the amplitude of the section when it was undriven
So from the question

=> 
=> 
=> 
=> 
Generally the amplitude of the section considered is mathematically represented as

=> 
=> 
=> 
=> 
Answer:

Explanation:
Given:
vertical height of oil coming out of pipe, 
diameter of pipe, 
length of pipe, 
density of oil, 
viscosity of oil, 
Now, since the oil is being shot verically upwards it will have some initial velocity and will have zero final velocity at the top.
<u>Using the equation of motion:</u>

where:
v = final velocity
u = initial velocity
Putting the respective values:


<u>For Reynold's no. we have the relation as:</u>



Ok first of all we have to convert in km/hr=Speed
So 30min are 0.5hours
Then we use S= distance/time = 5km/0.5 hrs = 10km/hr —> Jill speed
Then S= d/t = 10km/0.5hrs = 20km/hr —> Scott speed
So Scott rode faster