Answer:
a) E = 0.0048 Volts
b) dA/dt = - 0.002285 m²/s
Explanation:
Given:
Area, A = 0.020 m²
Rate of change of magnetic field, dB/dt = 0.24 T/s
a) The magnitude of the emf induced (E) is given as:
E= A × (dB/dt)
on substituting the values in the above equation, we get
E = (0.020 m²) × (0.24 T/s)
or
E = 0.0048 Volts
b) Now, The induced emf when both the area and the magnetic field is varying
we have
E = B(dA/dt) + A(dB/dt)
Now, for the given case induced emf is zero i.e E = 0 and magnetic field B = 2.1 T
thus,
0 = (2.1 T)(dA/dt) + (0.020 m2)(0.24 T/s)
dA/dt = - 0.002285 m²/s
Hence, the area should be decreased at the rate of 0.002285 m²/s
Answer:
5.571 sec
Explanation:
angular frequency = √ (k/m) = √ (49.3 / 5) = 3.14 rad/s
Period To = 2π / angular frequency
Period To = 2π/3.14 = 2 × 3.14 / 3.142 = 2.00 sec which you got
T measured by the observer = To / (√ (1 - (v²/c²))) = 2 / √( 1 - 0.871111) = 2 / 0.35901 = 5.571 sec
t=2.00/(1-√((2.80*10^8)^2/(3.00*10^8)^2))= should have been ( To / (√ (1 - (v²/c²))). where To = 2.00 sec
Yes, they seem right to me.
(Example 1 )
<span>If the Voltage that furnishes the current is an ideal (no internal resistance) Voltage source. Then; </span>
<span>V/R = i </span>
<span>V/2R = i/2 If external resistance doubles, current reduced to 1/2 of original value </span>
<span>V/3R = i/3 If external resistance triples, current reduced to 1/3 of original value </span>
<span>(Example 2) </span>
<span>But if the Voltage that furnishes the current is a practical [contains an internal resistance (Ri)] Voltage source. Then the current is a function of the Voltage source`s internal resistance, which does not double nor triple, plus the external resistance which is being doubled and tripled. </span>
<span>V/(R + Ri) = i </span>
<span>V/(2R + Ri) = greater than i/2 but less than I. </span>
<span>V/(3R + Ri) = greater than i/3 but less than i/2</span>
Answer:
Masa, m = 0.088 kg
Explanation:
Given the following data;
Temperatura inicial = 30°C
Temperatura final = 120°C
Capacidad calorífica específica = 138J/kg.K
Calor absorbido, Q = 4400 cal.
Para encontrar la masa;
La capacidad calorífica viene dada por la fórmula;
Dónde;
Q representa la capacidad calorífica o la cantidad de calor.
m representa la masa de un objeto.
c representa la capacidad calorífica específica del agua.
dt representa el cambio de temperatura.
dt = T2 - T1
dt = 120 - 30
dt = 90°C to kelvin = 273 + 90 = 363K
Sustituyendo en la fórmula, tenemos;
Masa, m = 0.088 kg
