Wow! Very simple. Use the equation for momentum which is p=mv. You know your momentum and velocity, so do 120=m(4), now solve for m, which is 30. The mass of the child is 30 kg
The size of the disc will Increase
The hole will enlarge in proportion to the metal if the disc is homogeneous and isotropic (the same in all directions). This is evident because, since the hole's edge is constructed of metal, the thermal expansion equation dL=LdT holds true for all lengths related to the metal, including the circle of the hole. Additionally, if the diameter of the hole increases, so does its circumference.
The analysis becomes more challenging if your disc has distinct areas formed of various metal kinds or if the metal that makes up your disc has an anisotropic crystal structure, meaning that it expands by different amounts in different directions. But given the total change in size is still an expansion, I believe the hole would become bigger in all scenarios.
Hence ,The size of the disc will Increase
Learn more about Metal disc here :
brainly.com/question/15314981
#SPJ4
Answer:
C) 2
Explanation:
The amount of centimeters is about 2.5 centimeters in an inch
Answer:
Explanation:
Given:
- flow rate of water,
<em>∵Density of water is 1 kg per liter</em>
∴mass flow rate of water, 
- height of pumping,
- efficiency of motor drive,
- diameter of pipe,
<u>Now the power required for pumping the water at given conditions:</u>
<u>Hence the electric power required:</u>
<u>Flow velocity is given as:</u>
where: a = cross sectional area of flow through the pipe
