Answer:
First law of thermodynamic state that energy is always conserved, in other word, energy cannot be created or destroyed.
This means that energy can only transfer from one source to another.
For example, the electricity we used to power our phone didn't come from nowhere.
We charge our phone using the energy from the electricity from the outlet.
The outlet gets its energy from the power plant, who generated that energy from burning coal.
The coal they burned got their energy while they were alive as plants.
The plants got their energy from the sun.
The sun got its energy from other cosmic stuff and so on...
My point is that the energy we use will always cycle around. It doesn't come from thin air and it doesn't disappear into thin air either. This help keeps things balance because if energy is created out of thin air then the earth might just blow up. If energy gets erased into thin air then there'll be nothing to fuel life.
<span>Resistance of automobile light is equal to 12 ohms.
</span>Resistance = Voltage / Current
where
Voltage = 12 volts
Current = 1.0 Amperes
Resistance = 12 volts/ 1.0 amperes
Resistance = 12 ohms.
Automobile light has 12 ohms resistance when it is connected to 12volts battery with 1.0 ampere current.
Answer:
1) 3.07kgm/s
2) 5.56kgm/s
3) 76.16N
4) 4.33kgm/s
5) 0.57s
6) -8.66J
Explanation:
Given
m = 0.221kg
v = 13.9m/s
θ = 25°
t = 0.073s
1) to get the magnitude of the initial momentum is the racquet ball. We use the formula,
P(i) = mv(i)
P(i) = 0.221 * 13.9
P(i) = 3.07kgm/s
2) Magnitude of the change in momentum of the ball,
P(i,x) = P(i) cos θ
P(i,x) = 3.07 * cos25
P(i,x) = 3.07 * 0.9063
P(i,x) = 2.78
ΔP = 2P(i,x)
ΔP = 2 * 2.78 = 5.56kgm/s
3) magnitude of the average force exerted by the wall,
F(ave) = ΔP/Δt
F(ave) = 5.56/0.073
F(ave) = 76.16N
4) ΔP(z) = mv(f) - mv(i)
ΔP(z) = 0.221*-7.8 - 0.221*11.8
ΔP(z) = -1.72 - 2.61
ΔP(z) = 4.33kgm/s
5) F(ave) = ΔP/Δt
Δt = ΔP/F(ave)
Δt = 4.33 / 76.16
Δt = 0.57s
6) KE(i) = 0.5mv(i)²
KE(f) = 0.5mv(f)²
ΔKE = 0.5m[v(f)² - v(i)²]
ΔKE = 0.5 * 0.221 [(-7.8)² - 11.8²]
ΔKE = 0.1105 ( 60.84 - 139.24 )
ΔKE = 0.1105 * -78.4
ΔKE = -8.66J
The physician changed the medication order because the infection was refractory, which means that the infection was resistant to treatment.