Answer:
D) sudden and irresistible on sets of sleep during normal waking periods
Explanation:
D because Narcolepsy (sudden and irresistible on sets of sleep during normal waking periods) is a part of insomnia
Answer: Always accelerates in a downward direction
Explanation: Gravity is pulling the ball downward
<h2>
a) Equivalent resistance is 143 Ω</h2><h2>
b) Potential difference is 71.5 V</h2>
Explanation:
When resistors are connected in series, effective resistance is given by

Here
R₁ = 21Ω
R₂ = 58Ω
R₃ = 64Ω
a) 
Equivalent resistance is 143 Ω
b) We know
Potential difference = Current x Resistance
V = IR
I = 0.5 A
R = 143Ω
Substituting
V = 0.5 x 143 = 71.5 V
Potential difference is 71.5 V
Explanation:
The critical velocity is that velocity of liquid flow, up to which its flow is streamlined (laminar)& above which its flow becomes turbulent. It's denoted by Vc & it depends upon: Coefficient of viscosity of liquid (η) Density of liquid. Radius of the tube.
The statement that describes the magnetic field inside a bar magnet is as follows: it points from north to south.
<h3>What is a bar magnet?</h3>
A bar magnet is a permanent magnet of rectangular shape.
A magnet generally possess a magnetic field, which is a condition in the space around a magnet which there is a detectable magnetic force and the presence of two magnetic poles.
A bar magnet like every other magnet possesses a magnetic field that points from the north pole to the south pole.
Learn more about magnets at: brainly.com/question/13026686
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