Answer:
Explanation:
The rms voltage = 140/√2 = 140/1.414 = 99 V.
Reactance of inductor = wL = 2 X 3.14 X 100 X 113 X 10⁻³ =70.96 ohm.
Total resistance in terms of vector = 50+70.96j
j is imaginary unit number
Magnitude of this resistance = √ 50² + 70.96² = 86.80 ohm
current in resistance (rms) ( I ) = 99/86.80 = 1.14 A.
Power dissipated in resistor = I² R = 1.14 X 1.14 X 50 = 65 W( approx)
Explanation:
They will have not much control over their speed or rotational energy. they will carry a lot of gravitation potential energy which will get converted to kinetic energy as they fall through the atmosphere. They will reach their terminal velocity, the fastest they can travel with earth's gravity before they pull their parachute, when they use a parachute to extend their surface area, increasing wind resistance. this allows them to land safely.
Answer:
HENCE (3) IS ANSWER
Explanation:
α =ΔL/(LO×Δ T) or ΔL= α(LO×Δ T)
HERE ΔL IS CHANGE IN LENGTH, Lo is original length , α is coefficient of linear expansion , Δ T is change in temperature
α= 11 x 10 ^-6/°C , Δ T = 19-20 = -1°C
hence
ΔL= 11 x 10 ^-6×10×-1
= - 11×10^-5
MINUS SIGN SHOWS SHORTER
HENCE (3) IS ANSWER
Answer:
<h2>a) 496N</h2><h2>b) 50.56kg</h2><h2>c) 1.90m/s²</h2>
Explanation:
According to newton's secomd law, ∑F = ma
∑F is the summation of the force acting on the body
m is the mass of the body
a is the acceleration
Given the normal force when the elevator starts N1 = 592N
Normal force after the elevator stopped N2 = 400N
When the elevator starts, its moves upward, the sum of force ∑F = Normal (N)force on the elevator - weight of the person( Fg)
When moving up;
N1 - Fg = ma
N1 = ma + Fg ...(1)
Stopping motion of the elevator occurs after the elevator has accelerates down. The sum of forces in this case will give;
N2 - Fg = -ma
N2 = -ma+Fg ...(2)
Adding equation 1 and 2 we will have;
N1+N2 = 2Fg
592N + 400N = 2Fg
992N 2Fg
Fg = 992/2
Fg = 496N
The weight of the person is 496N
<em>\b) To get the person mass, we will use the relationship Fg = mg</em>
g = 9.81m/s
496 = 9.81m
mass m = 496/9.81
mass = 50.56kg
c) To get the magnitude of acceleration of the elevator, we will subtract equation 1 from 2 to have;
N1-N2 = 2ma
592-400 = 2(50.56)a
192 = 101.12a
a = 192/101.12
a = 1.90m/s²