Answer:
20.42 N/m
Explanation:
From hook's law,
F = ke ......................... Equation 1
Where F = Force applied to the spring., k = spring constant, e = extension.
Make k the subject of the equation,
k = F/e ................. Equation 2
Note: The force on the spring is equal to the weight of the mass hung on it.
F = W = mg.
k = mg/e................ Equation 3
Given: m = 250 g = 0.25 kg, e = 37-25 = 12 cm = 0.12 m.
Constant: g = 9.8 m/s²
Substitute into equation 3
k = (0.25×9.8)/0.12
k = 20.42 N/m.
Hence the spring constant = 20.42 N/m
Phase 1. Forethought/preaction—This phase precedes the actual performance; sets the stage for action; maps out the tasks to minimize the unknown; and helps to develop a positive mindset. Realistic expectations can make the task more appealing. Goals must be set as specific outcomes, arranged in order from short-term to long-term. We have to ask students to consider the following:
<span>When will they start?Where will they do the work?How will they get started?<span>What conditions will help or hinder their learning activities are a part of this phase?
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Phase 2. Performance control—This phase involves processes during learning and the active attempt to utilize specific strategies to help a student become more successful.
We have to ask students to consider the following:
<span>Are students accomplishing what they hoped to do?Are they being distracted?Is this taking more time than they thought?Under what conditions do they accomplish the most?What questions can they ask themselves while they are working?<span>How can they encourage themselves to keep working (including self-talk—come on, get your work done so you can watch that television show or read your magazine!)
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Phase 3. Self-reflection—This phase involves reflection after the performance, a self-evaluation of outcomes compared to goals.
We have to ask students to consider the following:
<span>Did they accomplish what they planned to do?Were they distracted and how did they get back to work?Did they plan enough time or did they need more time than they thought?<span>Under what conditions did they accomplish the most work.
Hope this helps!!!!!
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Whatever hunts the wolfs will become famished and have a population decline while whatever the wolf hunts will have a population growth since there are less predators
Answer:
The marble was moving in a projectile and the speed of the engine was 2.716 m/s
Explanation:
The vertical component of the marble's flight path relative to the train
is given by the equation y(t) = v*t - (4.9)*t^2,
where, v is the initial upward velocity of the marble relative to the train.
So with y(1) = v - 4.9 = 0 we have
v = 4.9 m/s.
The marble will reach maximum height after 0.5 seconds, at which the
height will be y(0.5) = (4.9)*(0.5) - (4.9)*(0.5)^2 = (4.9)*(0.25) = 1.225 m.
Now, the marble has a vertical velocity component of 4.9 m/s and a horizontal velocity component
of V m/s such that tan(61) = 4.9 / V
V = 4.9 / tan(61) = 2.716 m/s
This horizontal velocity component of the marble is the same as the
speed of the train i.e. 2.716 m/s.
