**Answer:**

** 9,000 kg/ms^2**

**Explanation:**

The computation of the pressure fall across the valve is shown below:

It is to be computed by using the following formula

where,

= Fall in pressure

k = Coefficent loss

P = Loss of density

V = velocity of water

But before reach to the final solution first we have to determine the loss of density which is

Now put all other values to the given formula

So,

**Answer:**

I think 0.89 m/s... I'm not 100% sure.

**Explanation:**

Answer:

2.89 m/s²

Explanation:

Using the equation of kinematics

v²=u²+2as

Where v is the final velocity, u is initial velocity, a is acceleration and s is the distance covered.

For the first 50m, s is therefore 50 m, v is given as 17 m/s, u=0 m/s since it is from stop. By substitution

17²=0²+2*50*a

17²=100a

a=17²/100=2.89 m/s²

A mechanical wave is a wave that is not capable of transmitting its energy through a vacuum. Mechanical waves require a medium in order to transport their energy from one location to another. A sound wave is an example of a mechanical wave.