The speed of an object at rest is 0 m/s. We can use logic to figure this out. Hope this helps!
Answer:
<h2>The current required winding is
</h2>
Explanation:
We can use the expression B=μ₀*n*I-------1 for the magnetic field that enters a coil and
n= N/L (number of turns per unit length)
Given data
The number of turns n= 1200 turns
length L= 0.42 m
magnetic field B= 1*10^-4 T
μ₀= 
Applying the equation B=μ₀*n*I
I= B/μ₀*n
I= B*L/μ₀*n
Answer:
1050 possible selections
Explanation:
<em>Number of red balls = 7</em>
<em>Number of blue balls = 10</em>
<em>Let blue balls be B and red balls be R</em>
<em>four balls are to be selected. At least three must be blue.</em>
the first combination is 4blue 0red
second combination is 3blue 1red
(10C4*7C0 + 10C3*7C1)
210 *1 +120 *7
210+840
=1050 possibilities
<h3><u>
For the aceleration:</u></h3>
First, let's find the resultant, and <u>applicate 2nd law of Newton</u> using the resultant, so:
R = ma
F - Ff = ma
Data:
F = Force = 1150 N
Ff = Friction force = 490 N
m = Mass = 150 kg
a = Aceleraction = ?
Replacing according our data:
1150 N - 490 N = 150 kg * a
660 N = 150 kg * a
660 N / 150 kg = a
a = 4,4 m/s² ← Aceleration of the object
<h3><u>For the normal force:</u></h3>
The normal force IS NOT the resultant force, the normal force's the force between the ground and the object, in another words, is the weight of the object, and for the weight:
w = mg
w = 150 kg * 10 m/s²
w = 1500 N ← Normal force between object and ground.
