Answer:

Explanation:
The ratio of pressure 2 to 1 us 5.48/1= 5.48 rounded off as 5.5.
Referring to table A.2 of modern compressible flow then 
Also
and making
the subject of the formula then
Making reference to
diagram then

Answer:


Explanation:
In order to calculate the equivalent spring constant we need to use the next formula:

Replacing the data provided:


Finally, to calculate the frequency of oscillation we use this:

Replacing m and k:

In soccer, the ball is potential energy. When you kick the ball, it becomes kinetic energy.
Answer:
Force = 35 N
Explanation:
From Newton's third law of motion, the boy must apply a force greater than the weight of the sled to lift it.
weight of sled = mg
where m is its mass and g the force of gravity on it.
weight of sled = 50 N
Force applied by the boy on the sled = 15 N
Since the force applied on the sled by the boy is lesser than the weight of the sled, then;
Force that the sled exerts on the student = 50 - 15
= 35 N
The force exerted by the sled on the student is 35 N.