Answer:
Coring is a defect in an alloy (e.g., a copper nickel alloy) that occurs when a heated alloy is cooled too fast for diffusion to occur.
Explanation:
Answer:
x_total = 0.17m
Explanation:
We can treat this exercise with the kinematics equations, where in the first part it is accelerated and in the second it is a uniform movement.
Let's analyze accelerated motion
The time that lasts is t = 20 10⁻³ s, the initial speed is zero (v₀ = 0), let's find the length that advances
x₁ = v₀ t + ½ a t²
x₁ = ½ a t²
x₁ = ½ 210 (20 10⁻³)²
x₁ = 4.2 10⁻² m
let's find the speed for the end of this movement
v = v₀ + a t
v = 0 + 210 20 10⁻³
v = 4.2 m / s
with this speed we can find the distance that the uniform movement
x₂ = v t2
x₂ = 4.2 30 10⁻³
x₂ = 1.26 10⁻¹ m
x₂ = 0.126m
the total distance traveled is
x_total = x₁ + x₂
x_total = 0.0420 +0.126
x_total = 0.168m
Let's reduce the significant figures to two
x_total = 0.17m
The correct answer is erosion.
A yo yo in someone’s hand. All of the other options are kinetic energy. Remember, potential energy is when things are at a stop. Kinetic energy is when things are moving.
Answer:
10.9 m
Explanation:
We can solve the problem by using the law of conservation of energy.
The initial mechanical energy is just the kinetic energy of the ball:
![E = K_i = \frac{1}{2}mu^2](https://tex.z-dn.net/?f=E%20%3D%20K_i%20%3D%20%5Cfrac%7B1%7D%7B2%7Dmu%5E2)
where m is the mass of the ball and u = 16.9 m/s the initial speed.
At a height of h, the total mechanical energy is sum of kinetic energy and gravitational potential energy:
![E=K_f + U_f = \frac{1}{2}mv^2 + mgh](https://tex.z-dn.net/?f=E%3DK_f%20%2B%20U_f%20%3D%20%5Cfrac%7B1%7D%7B2%7Dmv%5E2%20%2B%20mgh)
where v is the new speed, g is the gravitational acceleration, h is the height of the ball.
Due to the conservation of energy,
(1)
Here, at a height of h we want the speed to be 1/2 of the initial speed, so
![v=\frac{1}{2}u](https://tex.z-dn.net/?f=v%3D%5Cfrac%7B1%7D%7B2%7Du)
So (1) becomes
![u^2 = (\frac{u}{2})^2+2gh\\\frac{3}{4}u^2 = 2gh](https://tex.z-dn.net/?f=u%5E2%20%3D%20%28%5Cfrac%7Bu%7D%7B2%7D%29%5E2%2B2gh%5C%5C%5Cfrac%7B3%7D%7B4%7Du%5E2%20%3D%202gh)
So we can find h:
![h=\frac{3u^2}{8g}=\frac{3(16.9 m/s)^2}{8(9.8 m/s^2)}=10.9 m](https://tex.z-dn.net/?f=h%3D%5Cfrac%7B3u%5E2%7D%7B8g%7D%3D%5Cfrac%7B3%2816.9%20m%2Fs%29%5E2%7D%7B8%289.8%20m%2Fs%5E2%29%7D%3D10.9%20m)