18:4 can be written as
9:2<---- when reduced
The answer is D) Cyclones. I am 100% sure on this one, so yeah. Hope this helps, and good luck. :D
We have
y=78.4 m and the distance, x=2400 m
we need to find out the time in the air, t=√2y/a
where a is 9.8 m/s²
t=√ 2*(-78.4)/-9.8 m/s²= √ -156.80/ -9.8 =√16=4s
speed of the bullet will be
v=x/t= 2400/4= 600m/s
Answer:
Kinetic energy is not made; it is a result of energy transformation
Explanation:
Let's discuss what happens to the ball when it is on top of the mountain and rolls down.
Initially the ball has a total mechanical energy, which at this point is potential.
Em₀ = U = mg h
When the ball starts to roll down, part of this potential energy will be transformed into kinetic energy.
Em = K + U = ½ m v² + mg y
but mechanical energy is conserved.
The presence of the grass introduces a force in the opposite direction that creates a friction force work (not conservative), for which the total mechanical energy decreases
W_{friction}= Emf - Emo
When examining the answers, the one that best describes Lana's error is:
Kinetic energy is not made; it is a result of energy transformation
<span> (13.89 - 5.56) m/s /30 s = 8.33 / 30 = 0.278 m/s^2 </span>
<span>F = MA </span>
<span>F = 150 kg * 0.278 = 41.65 N </span>
<span>#2) Newton's Equations of motion </span>
<span>distance = 0.5 * acceleration * time^2 + original velocity * time </span>
<span>velocity = acceleration * time + original velocity </span>
<span>First we need acceleration </span>
<span>F = MA </span>
<span>7 N = 0.4 kg*A (NOTE: I converted to consistent units: kg, m, s) </span>
<span>A = 7/.4 = 17,5 m/s^2 </span>
<span>V = at + Vo </span>
<span>80 m/s = 17.5 /s^2 * t + 0 (Started at rest) </span>
<span>80 = 17.5 t </span>
<span>t = 4.57 s </span>
<span>#3 </span>
<span>First we need the weight of the book on the floor </span>
<span>F = MA (A = 9.8 m/s^2 the acceleration of gravity) </span>
<span>F = 0.4 kg * 9.8 m/s^2 = 3.92 N </span>
<span>Now we need the Net Force on the book slowing it down (A = - 1.5 m/s^2) </span>
<span>F = MA </span>
<span>F = 0.4 kg * 1.5 m/s^2 = 0.6 N </span>
<span>===> Friction is 0.6 N greater than your push or 5.6 N </span>
<span>Weird!!! That means friction is greater than the weight of the book </span>
<span>Mu (coff of friction) = Friction Force/Weight = 5.6 / 3.92 = 1,43 ( Nonsense answer) </span>
<span>#4 We can do as a ratio </span>
<span>70/400 = 1500/x </span>
<span>70 x = 600,000 </span>
<span>x = 8,571 N</span>